Afforestation of European landscapes: How do different farmer types respond to EU agri-environmental schemes?   总被引：1，自引：0，他引：1  

Søren Præstholm  Anette Reenberg  Søren Pilgaard Kristensen 《GeoJournal》2006,67(1):71-84

This paper investigates how different types of farmers manage the landscape with primary emphasis on farmland afforestation, planned landscape changes, and the extent to which EU agri-environmental schemes take farm type specific characteristics into account in information strategies. The empirical data concern landscape practices of more than 2,000 landowners in 16 European areas in eight countries who were surveyed using quantitative questionnaires. Supplementary in-depth interviews were conducted for two case areas in Denmark to further investigate the role of the policy information environment. The analysis is based on a categorization of the farmers into hobby, part-time, full-time and retired farmers. This study shows that hobby farmers constitute a high proportion of landowners and manage a large part of the rural landscape. At the same time, hobby farmers are relatively more interested in landscape changes and differ from other landowners by considering farmland afforestation more often than full-time landowners, for example. Yet, 40% of the hobby farmers who are considering farmland afforestation are not familiar with the agri-environmental scheme for farmland afforestation. One reason may be their low membership rate in traditional information networks such as farmers’ or foresters’ associations, as revealed by the in-depth analysis of the cases in Denmark. Thus, it is proposed that policy impact may be improved if farmer type specific differences are explicitly taken into account in the scheme logistics for EU agri-environmental schemes.  相似文献   

Astronomical refraction and airmass     

L. Kahl Kristensen 《Astronomische Nachrichten》1998,319(3):193-198

Standard astronomical refraction is approximated to ±1/2″ by a simple procedure valid to the horizon. In the approximation where absroption and refraction are proportional to the density of the air the computations of refraction and airmass should not be separated.  相似文献   

Leaf removal by sesarmid crabs in Bangrong mangrove forest, Phuket, Thailand; with emphasis on the feeding ecology of Neoepisesarma versicolor     

Nalinee Thongtham  Erik Kristensen  Som-Ying Puangprasan 《Estuarine, Coastal and Shelf Science》2008,80(4):573-580

Field measurements on leaf removal by populations of sesarmid crabs at different locations in the Bangrong mangrove forest, Phuket, Thailand, indicated that crabs on average can remove 87% of the daily leaf litter fall by ingestion or burial. The removal rate is correlated positively with the number of crab burrows and negatively with tidal inundation time. The results from the field were supplemented with observations on the behavior of Neoepisesarma versicolor in laboratory microcosms and a mangrove mesocosm. N. versicolor feeds primarily at night and total time spent feeding was up to an order of magnitude higher in the artificial microcosms than under simulated in situ conditions in the mesocosm. Most of the time during both day and night was spent resting near the entrance or inside burrows. N. versicolor mainly feeds on mangrove leaves and scraps of food material from the sediment surface. This is supported by examinations of stomach content, which showed that 62% is composed of higher plant material and 38% of detritus and mineral particles from the sediment. The nutritive value of leaves and detritus is insufficient to maintain crab growth. Sesarmid crabs may instead obtain the needed nutrients by occasional consumption of nitrogen-rich animal tissues, such as carcasses of fish and crustaceans, as indicated by the presence of animal remains in the stomach and the willingness of crabs to consume fish meat. Laboratory experiments on leaf consumption and leaf preferences of N. versicolor indicate that they preferentially feed on brown leaves, if available, followed by green and yellow leaves. If all species of sesarmid crabs in the Bangrong mangrove forest consume leaves at the same rate as N. versicolor, they could potentially ingest 52% of the total litter fall.  相似文献   

On the definition of asteroid magnitudes     

L. K. Kristensen 《Astronomische Nachrichten》1987,308(2):135-138

The problem of a sharp definition of two photometric parameters for asteroids in the presence of empirical phase functions is discussed. In a rational magnitude system advantage should be taken of the nearly linear phase curve.  相似文献   

Planning with complexity—how do we deal with stakeholder and spatial heterogeneity in land use planning?     

Torben Birch-Thomsen  Søren P. Kristensen 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):23-37

Geografisk Tidsskrift, Danish Journal of Geography 105(2):23–37, 2005

As a reaction to the 'top-down 'approach to rural development during the 1970's and 1980's, and in line with the increased focus on ‘putting farmers first’ (bottom-up) through local participation, new and integrated approaches to natural resource management (NRM) have been launched to generate sustainable development. This paradigmatic change has greatly influenced land use planning. Some of the implications involved in this change are discussed in this paper and based on empirical data from Tanzania and Botswana. In this paper we will discuss three critical issues related to land use planning for sustainable NRM: the complexity of livelihood strategies at the local level, the role of different stakeholder interests and the importance of spatial scale considerations. The discussion emphasizes the importance of understanding that the different and often erratic resource endowment of the rural households influences the strategies these households follow in order to meet their overall needs, rather than ‘simply’ maximizing agricultural yields. Furthermore, the importance of spatial scale, in relation to both different stakeholder interests and their needs will be discussed. The paper highlights the need to take community heterogeneity into consideration in land use planning if sustainable NRM is to be achieved in the future.  相似文献   

Land system changes in the context of urbanisation: Examples from the peri-urban area of Greater Copenhagen     

Anne Gravsholt Busck  Søren Pilgaard Kristensen  Søren Præstholm  Anette Reenberg  Jørgen Primdahl 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):21-34

Peri-urban areas are characterised by great heterogeneity and rapid changes of land use. Furthermore, population composition changes as peri-urban areas offer attractive residential alternatives to city centres or more remote locations. The dynamic processes leave peri-urban areas in an in-between situation, neither city nor countryside and home to a range of functions, spanning from agricultural production to residential and recreational areas. The paper investigates the urbanisation of agricultural areas in the Greater Copenhagen region based on quantitative data collected on agricultural properties in nine study areas between 1984 and 2004. The overall conclusion is that agricultural land use has continued largely unaffected by the processes of urbanisation. However, most of the production is concentrated on a few very large full-time farms. In addition, the economic activities have been greatly diversified over the last three decades. The structural components of the areas (land use and landscape elements) thus appear more resilient than the socio-economic system (declining number of full-time farmers and increasing number of owners engaged in other gainful activities). However, at some point this discrepancy will disappear and rapid land use changes may be expected.  相似文献   

Elsterian‐Holsteinian deposits at Kås Hoved,northern Denmark: sediments,foraminifera, ostracods,and stable isotopes     

Karen Luise Knudsen  Claus Ditlefsen  David N. Penney  Peter Kristensen  Christian Kronborg  Jón Eiríksson 《Boreas: An International Journal of Quaternary Research》2014,43(1):251-271

The coastal cliff section at Kås Hoved in northern Denmark represents one of the largest exposures of marine interglacial deposits in Europe. High‐resolution analyses of sediments, foraminifera, ostracods, and stable isotopes (oxygen and carbon) in glacial‐interglacial marine sediments from this section, as well as from two adjacent boreholes, are the basis for an interpretation of marine environmental and climatic change through the Late Elsterian‐Holsteinian glacial‐interglacial cycle. The overlying glacial deposits show two ice advances during the Saalian and Weichselian glaciations. The assemblages in the initial glacier‐proximal part of the marine Late Elsterian succession reveal fluctuations in the inflow of sediment‐loaded meltwater to the area. This is followed by faunal indication of glacier‐distal, open marine conditions, coinciding with a gradual climatic change from arctic to subarctic environments. Continuous marine sedimentation during the glacial‐interglacial transition is presumably a result of a large‐scale isostatic subsidence caused by the preceding extended Elsterian glaciation. The similarity of the climatic signature of the interglacial Holsteinian and Holocene assemblages in this region indicates that the Atlantic Ocean circulation was similar during these two interglacials, whereas Eemian interglacial assemblages indicate a comparatively high water temperature associated with an enhanced North Atlantic Current. The foraminiferal zones are correlated with other Elsterian‐Holsteinian sites in Denmark, as well as those in the type area for the Holsteinian interglacial in northern Germany and the southern North Sea. Correlation of the NW European Holsteinian succession with the marine isotope stages MIS 7, 9 or 11 is still unresolved.  相似文献   

From agriculture to nature – a study of drivers of land use change in a peri-urban landscape     

Anne Gravsholt Busck  Søren Bech Pilgaard Kristensen 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2014,114(1):41-58

In this article, we investigate drivers behind land use changes in a peri-urban landscape. The research focuses on the motives and factors behind landowners’ decision-making in relation to land use changes, with the objective of improving our knowledge of the dynamics of land use change processes on farmland. An actor-centred conceptual framework is developed on the basis of the concept of lenses of decision-making. Data on farm and farmer characteristics were collected through a survey conducted in Roskilde Municipality, Denmark, a peri-urban landscape with a high level of landscape dynamics. A logistic regression analysis was used to analyse the relationship between nine purposively selected farm and farmer characteristics and the landscape activities of 93 landowners in the municipality. The results indicate that small farms, farms without livestock and landowners with a basic level of education are less likely to engage in landscape activities. A cluster analysis was used to analyse patterns of motives associated with land use changes. The results correspond with the intrinsic interests and family considerations suggested in the lenses of the decision-making framework, and in addition shows that the desire to improve the qualities of the property was the dominant motive.  相似文献   

Residents’ urbanized landscape preferences in rural areas reveal the importance of naturalness-livability contrast     

Yang  Gaoyuan  Yu  Zhaowu  Luo  Tao  Lone  Søderkvist Kristensen 《地理学报(英文版)》2022,32(8):1493-1512

Journal of Geographical Sciences - Urbanization has caused significant landscape changes in rural areas, leading to the emergence of urbanized landscapes (ULs), which have been generally criticized...  相似文献   

A morphometric analysis of tunnel valleys in the eastern North Sea based on 3D seismic data     

Thomas B. Kristensen  Mads Huuse  Jan A. Piotrowski  Ole R. Clausen 《第四纪科学杂志》2007,22(8):801-815

A 1250 km² 3D seismic volume is used to provide a detailed spatial and geometrical analysis of fifteen Pleistocene tunnel valleys in the Danish North Sea. All the valleys are buried; they are up to 39 km long, 3–4 km wide and up to 350 m deep. The valleys are part of a vast tunnel valley province covering an area of some 0.5 million km² of the formerly glaciated lowland areas of North West Europe. The valleys consist of non‐branching, non‐anastomosing troughs; they exhibit strongly undulating bottom profiles with numerous sub‐basins and thresholds, and are characterised by adverse end slopes. Cross‐cutting relationships and theoretical considerations suggest the occurrence of seven major episodes of valley incision attributed to ice marginal oscillations within a few glacials. Calculations considering the valley end gradients and theoretical ice‐surface profiles suggest that the valleys were formed by pressurised subglacial meltwater erosion. Given a range of theoretical ice‐surface profiles, the adverse end slopes are well beyond the supercooling threshold, which suggests that the water was not in thermal equilibrium with the basal ice and that flow was concentrated in substantial conduits with sufficient mass and flux to maintain water temperature well above the freezing point. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献