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Wells of Experience : A pastoral land-use history of Omaheke, Namibia.Lindholm, Karl-Johan January 2006 (has links)
<p>The conventional view on the Kalahari in southern Africa expresses that the area is unsuitable for livestock herding. For this reason, it is argued that livestock herders avoided the Kalahari in the past and were only able to establish themselves in the later half of the twentieth century, when deep-reaching boreholes were introduced in the area. An effect of this concept was that the archaeological record of pastoralists in the Kalahari either was perceived as non-existent or received little attention from scientific enquiry.</p><p>Based on an archaeological survey in the Kalahari of the northeastern part of Namibia, the purpose of this study is to construct an alternative approach to the archaeology of livestock herding. The aim is to contribute to a better understanding of the areas unrecorded land-use history. </p><p>I depart from the notion that the main ecological constraint for dryland pastoralism is the availability of dry season water and fodder resources. For this reason, the fundamental basis for a pastoral land-use system is places that contain dry season resources. By reviewing recent ecological research, historical and anthropological accounts and previous archaeological research, I establish a link between livestock herders’ procurement of dry season key resources and the practice of digging wells. The link can be motivated from the pastoral ambition of accumulating livestock and high water requirements in the restrained dry season. On this basis, I suggest that artificial wells are useful indicators of pastoral land use in the Kalahari. </p><p>The most crucial task for the study is to address the archaeological visibility of pastoral well sites. By a research approach integrating the theoretical understanding of pastoralism and a methodology including ecology, archaeology, history and the knowledge of the people who keep livestock in the region today, the archaeological survey revealed 40 well sites, including nearly 200 well structures that have all been used for watering livestock. </p><p>However, it would be unfortunate if a study of pastoral wells would solely address the ecological foundation and the archaeological visibility of pastoralism. I suggest that the wells signify the labour of peoples with common or separate histories, with or without own herds, but probably talked about in relation to herds. I will also argue that the wells can be used for tracking and reconstructing a pastoral land-use system that predated the colonial era. Furthermore, the wells can be used to identify changes of the land-use that took place during the twentieth century, which involved that livestock herding was more or less abandoned in large parts of northwestern Kalahari. </p><p>The study surmises that the critical historical perspective is valuable for development projects and conservationist interventions active in the region, especially in the light of the recent trends in the dryland ecology, which shows a larger appreciation for the indigenous understanding of the management of dryland ecosystems. With modifications, the developed approach can be applicable for land-use historical research elsewhere in southern Africa.</p>
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Wells of Experience : A pastoral land-use history of Omaheke, Namibia.Lindholm, Karl-Johan January 2006 (has links)
The conventional view on the Kalahari in southern Africa expresses that the area is unsuitable for livestock herding. For this reason, it is argued that livestock herders avoided the Kalahari in the past and were only able to establish themselves in the later half of the twentieth century, when deep-reaching boreholes were introduced in the area. An effect of this concept was that the archaeological record of pastoralists in the Kalahari either was perceived as non-existent or received little attention from scientific enquiry. Based on an archaeological survey in the Kalahari of the northeastern part of Namibia, the purpose of this study is to construct an alternative approach to the archaeology of livestock herding. The aim is to contribute to a better understanding of the areas unrecorded land-use history. I depart from the notion that the main ecological constraint for dryland pastoralism is the availability of dry season water and fodder resources. For this reason, the fundamental basis for a pastoral land-use system is places that contain dry season resources. By reviewing recent ecological research, historical and anthropological accounts and previous archaeological research, I establish a link between livestock herders’ procurement of dry season key resources and the practice of digging wells. The link can be motivated from the pastoral ambition of accumulating livestock and high water requirements in the restrained dry season. On this basis, I suggest that artificial wells are useful indicators of pastoral land use in the Kalahari. The most crucial task for the study is to address the archaeological visibility of pastoral well sites. By a research approach integrating the theoretical understanding of pastoralism and a methodology including ecology, archaeology, history and the knowledge of the people who keep livestock in the region today, the archaeological survey revealed 40 well sites, including nearly 200 well structures that have all been used for watering livestock. However, it would be unfortunate if a study of pastoral wells would solely address the ecological foundation and the archaeological visibility of pastoralism. I suggest that the wells signify the labour of peoples with common or separate histories, with or without own herds, but probably talked about in relation to herds. I will also argue that the wells can be used for tracking and reconstructing a pastoral land-use system that predated the colonial era. Furthermore, the wells can be used to identify changes of the land-use that took place during the twentieth century, which involved that livestock herding was more or less abandoned in large parts of northwestern Kalahari. The study surmises that the critical historical perspective is valuable for development projects and conservationist interventions active in the region, especially in the light of the recent trends in the dryland ecology, which shows a larger appreciation for the indigenous understanding of the management of dryland ecosystems. With modifications, the developed approach can be applicable for land-use historical research elsewhere in southern Africa.
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Effects of Land-Use History on Soil Macro- and Trace Elements in the Southern Piedmont of North AmericaLi, Jianwei January 2009 (has links)
<p>Land use histories affect the rate and pattern of soil nutrients at regional and global scale. However, former studies have rarely focused on soil trace elements (B, Mn, Zn, Cu and Fe). In this study, we aimed at the long-term biogeochemical cycling pattern and spatial heterogeneity of soil trace elements in response to land use changes. We conducted experiment at Calhoun experiment forest in SC and surrounded relic hardwood forest, cultivated land and secondary pine forests with contrasting land use histories in a statistically rigorous and spatially explicit design. Our first study indicated that spatial heterogeneity is greatly reduced in many soil properties by agricultural practices, but that successional forest growth on previously cultivated soils re-structures heterogeneity of soil properties within a few decades. We document cases in which land use alters both the soil property's central tendencies and their heterogeneity (C, N, CN, Ca, K), and cases in which changes are apparent in central tendency but much less so in their heterogeneity (Db). In our second study, samples of the upper 0.6-m mineral soil archived in 1962 and 1997 revealed three cycling patterns: 1) Extractable B and Mn were significantly depleted because tree uptake of B and Mn from mineral-soil greatly outpaced resupplies from atmospheric deposition, mineral weathering, and deep-root uptake. 2) Extractable Zn and Cu changed little during forest growth, indicating that nutrient resupplies kept pace with accumulations by the aggrading forest. 3) Oxalate-extractable Fe increased substantially during forest growth, by about 10-fold more than accumulations in tree biomass. This study indicated that forest Fe cycling is qualitatively different from that of other macro- and micro-nutrients. Thirdly, our results revealed that long-term cultivation substantially diminished the activity of soil iron oxides relative to forest growth. Forest Fe cycling is derived from mineral soil weathering, which suggests a need to explore the underlying mechanisms by which bioturbation (e.g.earthworms) mediates transformations of iron bioavailability and oxidation of organic matter in soils. Overall, the wide range of responses to land use changes among the ecosystem's trace elements and other biogeochemical features illustrates the great dynamics of the soil system over time scales of decades to centuries.</p> / Dissertation
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Woody Plant Dynamics in a Sonoran Desert Ecosystem across Scales: Remote Sensing and Field PerspectivesBrowning, Dawn M. January 2008 (has links)
Historic land uses impose discernable legacy effects that may influence ecosystem function, a concern of particular importance in actively managed landscapes. In recent history (ca. 150 years) tree and shrub abundance has increased at the expense of native grasses in savannas and grasslands. The magnitude and patterns of change are spatially heterogeneous, highlighting the need for analytical approaches spanning multiple spatial scales, from individual plants to patches to landscapes. The overarching goal of this dissertation was to explore long-term dynamics associated with woody plant encroachment with aerial photography and field studies to examine cover, density, soils and land use history at the Santa Rita Experimental Range.The first study characterized patterns in woody cover change on contrasting soils over 60 years using aerial photography. Woody patch dynamics revealed encroachment and stabilization phases in woody plant proliferation. Soil properties reflected the rate at which uplands reached a dynamic equilibrium, but not the endpoint (ca. 35% cover). Fluctuations around dynamic equilibrium reflected net change in patch growth and acquiescence combined with colonization and mortality. Efforts to characterize changes in land cover will require patch-based assessments beyond coarse estimates of percent cover.The second study capitalized on historic field measurements of shrub canopies to validate estimates of shrub cover derived from the earliest aerial photography, quantified detection limitations of 1936 aerial photographs for mapping shrub cover, assessed species-specific contributions to percent cover, and translated detection limitations to proportions of velvet mesquite (Prosopis velutina var Woot.) biomass missed with 1930s aerial photography.The third study was a field-based approach investigating how livestock grazing influenced mesquite cover, density, biomass, and stand structure over 74 years. The study supplemented traditional statistical analysis of grazing effects with methods quantifying spatial autocorrelation structure of mesquite density by grazing treatment. The outcome re-affirmed the supposition that mesquite cover may be dynamically stable at ca 30%, and revealed that livestock grazing slowed the shrub encroachment process from 1932 to 2006, counter to expectation. Results indicate that shrub growth trajectories persist long-term. Overall, this work affirms the importance of land use legacies and long-term perspectives in rangeland shrub dynamics.
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Vägar till landskapet : om vägars tidrumsliga egenskaper som utgångspunkt för landskapsstudier /Qviström, Mattias, January 2003 (has links) (PDF)
Diss. Alnarp : Sveriges lantbruksuniv., 2003.
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COMPARING STAND COMPOSITION AND FLORISTIC QUALITY OF TWO ADJACENT UPLAND OAK-HICKORY WOODLANDS IN SOUTHERN ILLINOIS: OLD-GROWTH AND SECOND-GROWTH DYNAMICSKleiman, Leah Rose 01 August 2023 (has links) (PDF)
Illinois has no official parameters for old-growth oak-hickory (Quercus-Carya) forests despite oak-hickory being the historically dominant ecosystem in the forested parts of Illinois (Fralish, 1997; Thompson & Dessecker, 1997). The purpose of this study was to better understand the characteristics of old-growth oak-hickory stands, as well as make management recommendations for preserving the integrity of old-growth forests and shifting second-growth stands to old-growth status. Stand structure analysis was conducted in June and July of 2022 on an old-growth oak-hickory stand (Otey-Grisley Nature Preserve) and nearby second-growth oak-hickory stand (Grisley Woods Land and Water Reserve) near Pittsburg, Illinois using dendrochronology, various stand composition analyses, and floristic assessments to compare the two forests across multiple nodes of inquiry from their canopies to their ground layers. White oak (Quercus alba L.) was of higher importance in the more open old-growth canopy than the closed second-growth canopy which had more shagbark hickory (Carya ovata L.). The old-growth stand had higher floristic quality (mean Coefficient of Conservatism and adjusted Floristic Quality Index) and lower frequency of invasive species than the second-growth stand. The dominant white oak appear to have suppressed the hickories (Carya) for over a century on both sites. However, in the sapling and seedling layer, it appears the oaks and hickories are failing to recruit into the canopy on either site. The average age of the old-growth canopy is 67 years greater than that of the second-growth canopy, the majority of which seeded in after a heavy cut in the early 1940s. The second-growth site rapidly gained early successional species after the logging. The second-growth site could come to resemble the open oak dominated character of the old-growth site. However, this will require management with fire, thinning, and invasive species treatments. The old-growth, where sassafras (Sassafras albidum L.) is crowding the understory, will also require invasive species management, prescribed fire, and thinning if it is to remain the open oak-hickory woodland it is today.
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Floristic Survey of the Terrestrial Vascular Flora of Strouds Run State Park, Athens County, OhioHarrelson, Sarah 19 April 2005 (has links)
No description available.
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Efeito de borda em um contexto de Florestas Urbanas: Resultantes estruturais de usos pret?ritos do solo / Edge effect in urban forests: structural resultants of land use history.Monteiro, Flavia de Carvalho Dias 25 March 2008 (has links)
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Previous issue date: 2008-03-25 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPQ / The Atlantic Rain Forest is one of the world?s most endangered biomes. Long before its
discovery by western civilization, the forest had already been occupied and used by native
populations. The increasing occupation of this biome has generated landscapes composed of
a mosaic of forests of different ages that resulted from its usage and that overlap in space and
time. Remaining fragments are still subject to manmade impacts including edge effects.
Based on these concepts, a study was conducted aiming at understanding the edge effects, on
structure and composition, of two areas of Atlantic Rain Forest in the Pedra Branca State Park
in Rio de Janeiro, RJ; one located in the valley basins (Ca?ambe river basin), and the other at
the limit of the drainage (Grande river basin). At each area, were choosed two sites; one near
to the edge and other over 100m from the edge (forest interior). The sites were: valley basin?s
edge (Bfv), valley basin?s interior (Ifv), limit of the drainage?s edge (Bdd) and limit of the
drainage?s interior (Idd). Changes caused by the existence of a edge, included the assess of a
biotic edge effects, using for it changes in the species richness, individuals density, diameter
and height. Individual trees and shrubs with diameter at breast height (dbh) > 5 cm were
sampled within 32 plots of 10 x 10 m for a total sample size of 0.32 ha. The samples yielded
309 individuals of 77 species, 70 genera and 32 families. The total basal area was 28,89 m2/ha
and density was 966 ind./ha. Leguminosae, Meliaceae e Sapotaceae were found to be the
richest families. The number of total species is comparable to the referenced values for
preserved forests, inventoried in the southeast. The edges species richness (Bfv and Ifv)
similar to the interiors species richness (Ifv and Idd). Mean diameter varied form 32, 9 cm and
36,2 cm in the edges and 42,2 cm and 53,1 cm in the forests interiors. Probably, the sampled
edges finds itself in a state of natural regeneration and represents an inicial successional state,
different to the intermediary sucessional state in the interiors. The index of S?rensen
between the four sites may occurs due to the different slope orientation, geomorphologic
situation and land use history. / A Mata Atl?ntica ? um dos biomas mais amea?ados do mundo. Desde antes de sua descoberta
pelo ocidente, a floresta j? era utilizada e apropriada por popula??es nativas. Com a
intensifica??o da ocupa??o deste bioma, geraram-se paisagens compostas por mosaicos de
florestas de diferentes idades, provenientes de usos diversos, que se sobrep?em no tempo e no
espa?o. Os fragmentos remanescentes est?o ainda sujeitos a v?rios impactos antr?picos, tais
como os efeitos de borda. Desta forma, procura-se analisar como a din?mica homem-natureza
exerce suas influ?ncias na transforma??o da paisagem. Procurou-se compreender os efeitos de
borda na estrutura e composi??o de duas ?reas de Mata Atl?ntica, localizadas no Parque
Estadual de Pedra Branca na cidade do Rio de Janeiro, RJ; uma localizada no fundo de vale
(bacia do rio Ca?ambe) e a outra no divisor de drenagem (bacia do rio Grande). Em cada ?rea
de estudo, foram selecionados 2 s?tios amostrais; um adjacente ? borda e o outro distante a
cerca de 100 metros da borda (interior de floresta). Os quatro s?tios amostrais foram
denominados borda de fundo de vale (Bfv), interior de fundo de vale (Ifv), borda do divisor
de drenagem (Bdd) e interior do divisor de drenagem (Idd). As mudan?as provocadas pela
exist?ncia de uma borda envolveram avalia??es de efeitos biol?gicos, utilizando como
ferramenta a riqueza de esp?cies, a densidade, estrutura diam?trica e de tamanho dos
indiv?duos. Para a amostragem das ?reas, foram implantadas 32 parcelas, de 100 m? (0,32 ha),
sendo que o crit?rio de inclus?o adotado foi DAP ? 5 cm. Foram amostrados 309 indiv?duos
de 77 esp?cies, 70 g?neros e 32 fam?lias. A ?rea basal total foi de 28,89 m2/ha e densidade de
966 ind./ha. Leguminosae, Meliaceae e Sapotaceae apresentaram os maiores valores de
riqueza de esp?cies. O n?mero total de esp?cies amostradas foi compat?vel com forma??es
assemelhadas do sudeste Brasileiro. As bordas apresentaram uma riqueza de esp?cies pr?xima
? das ?reas interioranas. Os di?metros m?dios variaram entre 32,9 cm e 36,2 cm nas bordas e
42,2 cm e 53,1cm nos interiores de floresta. Provavelmente, as bordas amostradas encontramse
em est?gio de regenera??o natural, representando grupos sucessionais iniciais, distintos
daqueles que ocorrem no interior da floresta. A n?o similaridade das ?reas, aferida com o uso
do ?ndice de S?rensen mostrou que cada uma das ?reas ? constitu?da por conjuntos de
esp?cies caracter?sticas. Estes resultados podem ser atribu?dos ?s diferentes orienta??es de
encosta, situa??o geomorfol?gica e aos usos pret?ritos das ?reas.
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Efeito de borda em um contexto de florestas urbanas: resultantes estruturais de usos pret?ritos do solo / Edge effect in urban forests: structural resultants of land use historyDIAS, Flavia de Carvalho 25 March 2008 (has links)
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2008 - Flavia de Carvalho Dias.pdf: 1016485 bytes, checksum: c85fcc5f987d04ec4a9490cffdf1ebab (MD5) / Made available in DSpace on 2017-10-06T18:22:30Z (GMT). No. of bitstreams: 1
2008 - Flavia de Carvalho Dias.pdf: 1016485 bytes, checksum: c85fcc5f987d04ec4a9490cffdf1ebab (MD5)
Previous issue date: 2008-03-25 / CNPq / The Atlantic Rain Forest is one of the world?s most endangered biomes. Long before its discovery by western civilization, the forest had already been occupied and used by native populations. The increasing occupation of this biome has generated landscapes composed of a mosaic of forests of different ages that resulted from its usage and that overlap in space and time. Remaining fragments are still subject to manmade impacts including edge effects. Based on these concepts, a study was conducted aiming at understanding the edge effects, on structure and composition, of two areas of Atlantic Rain Forest in the Pedra Branca State Park in Rio de Janeiro, RJ; one located in the valley basins (Ca?ambe river basin), and the other at the limit of the drainage (Grande river basin). At each area, were choosed two sites; one near to the edge and other over 100m from the edge (forest interior). The sites were: valley basin?s edge (Bfv), valley basin?s interior (Ifv), limit of the drainage?s edge (Bdd) and limit of the drainage?s interior (Idd). Changes caused by the existence of a edge, included the assess of a biotic edge effects, using for it changes in the species richness, individuals density, diameter and height. Individual trees and shrubs with diameter at breast height (dbh) > 5 cm were sampled within 32 plots of 10 x 10 m for a total sample size of 0.32 ha. The samples yielded 309 individuals of 77 species, 70 genera and 32 families. The total basal area was 28,89 m2/ha and density was 966 ind./ha. Leguminosae, Meliaceae e Sapotaceae were found to be the richest families. The number of total species is comparable to the referenced values for preserved forests, inventoried in the southeast. The edges species richness (Bfv and Ifv) similar to the interiors species richness (Ifv and Idd). Mean diameter varied form 32, 9 cm and 36,2 cm in the edges and 42,2 cm and 53,1 cm in the forests interiors. Probably, the sampled edges finds itself in a state of natural regeneration and represents an inicial successional state, different to the intermediary sucessional state in the interiors. The index of S?rensen between the four sites may occurs due to the different slope orientation, geomorphologic situation and land use history. / A Mata Atl?ntica ? um dos biomas mais amea?ados do mundo. Desde antes de sua descoberta pelo ocidente, a floresta j? era utilizada e apropriada por popula??es nativas. Com a intensifica??o da ocupa??o deste bioma, geraram-se paisagens compostas por mosaicos de florestas de diferentes idades, provenientes de usos diversos, que se sobrep?em no tempo e no espa?o. Os fragmentos remanescentes est?o ainda sujeitos a v?rios impactos antr?picos, tais como os efeitos de borda. Desta forma, procura-se analisar como a din?mica homem-natureza exerce suas influ?ncias na transforma??o da paisagem. Procurou-se compreender os efeitos de borda na estrutura e composi??o de duas ?reas de Mata Atl?ntica, localizadas no Parque Estadual de Pedra Branca na cidade do Rio de Janeiro, RJ; uma localizada no fundo de vale (bacia do rio Ca?ambe) e a outra no divisor de drenagem (bacia do rio Grande). Em cada ?rea de estudo, foram selecionados 2 s?tios amostrais; um adjacente ? borda e o outro distante a cerca de 100 metros da borda (interior de floresta). Os quatro s?tios amostrais foram denominados borda de fundo de vale (Bfv), interior de fundo de vale (Ifv), borda do divisor de drenagem (Bdd) e interior do divisor de drenagem (Idd). As mudan?as provocadas pela exist?ncia de uma borda envolveram avalia??es de efeitos biol?gicos, utilizando como ferramenta a riqueza de esp?cies, a densidade, estrutura diam?trica e de tamanho dos indiv?duos. Para a amostragem das ?reas, foram implantadas 32 parcelas, de 100 m? (0,32 ha), sendo que o crit?rio de inclus?o adotado foi DAP ? 5 cm. Foram amostrados 309 indiv?duos de 77 esp?cies, 70 g?neros e 32 fam?lias. A ?rea basal total foi de 28,89 m2/ha e densidade de 966 ind./ha. Leguminosae, Meliaceae e Sapotaceae apresentaram os maiores valores de riqueza de esp?cies. O n?mero total de esp?cies amostradas foi compat?vel com forma??es assemelhadas do sudeste Brasileiro. As bordas apresentaram uma riqueza de esp?cies pr?xima ? das ?reas interioranas. Os di?metros m?dios variaram entre 32,9 cm e 36,2 cm nas bordas e 42,2 cm e 53,1cm nos interiores de floresta. Provavelmente, as bordas amostradas encontram-se em est?gio de regenera??o natural, representando grupos sucessionais iniciais, distintos daqueles que ocorrem no interior da floresta. A n?o similaridade das ?reas, aferida com o uso do ?ndice de S?rensen mostrou que cada uma das ?reas ? constitu?da por conjuntos de esp?cies caracter?sticas. Estes resultados podem ser atribu?dos ?s diferentes orienta??es de encosta, situa??o geomorfol?gica e aos usos pret?ritos das ?reas.
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Past and present management influences the seed bank and seed rain in a rural landscape mosaicAuffret, Alistair G., Cousins, Sara A. O. January 2011 (has links)
1. Seed bank and seed rain represent dispersal in time and space. They can be important sources of diversity in the rural landscape, where fragmented habitats are linked by their histories. 2. Seed bank, seed rain and above-ground vegetation were sampled in four habitat types (abandoned semi-natural grassland (ABA), grazed former arable field (FAF), mid-field islet (MFI) and grazed semi-natural grassland (SNG)) in a rural landscape in southern Sweden, to examine whether community patterns can be distinguished at large spatial scales and whether seed bank and seed rain are best explained by current, past or intended future vegetation communities. 3. We counted 54 357 seedlings of 188 species from 1190 seed bank and 797 seed rain samples. Seed bank, seed rain and above-ground vegetation communities differed according to habitat. Several species characteristic of managed grassland vegetation were present in the seed bank, seed rain and vegetation of the other habitats. 4. The seed banks of SNGs and the seed rain of the FAFs were generally better predicted by the surrounding above-ground vegetation than were the other habitat types. The seed rain of the grazed communities was most similar to the vegetation in the FAFs, while the seed banks of the abandoned grasslands most resembled the vegetation in SNGs. 5. Gap availability and seed input could be limiting the colonisation of target species in FAFs, while remnant populations in the seed bank and the presence of grassland specialists in the above-ground vegetation indicate that abandoned grasslands and mid-field islets could be valuable sources of future diversity in the landscape after restoration. 6. Synthesis and applications. SNG communities are able to form seed banks which survive land-use change, but their seed rain does not reflect their above-ground communities. It is important that grassland plants set seed. By connecting existing grasslands with restoration targets, increased disturbance in the target habitats would allow for colonisation via the seed bank or seed rain, while decreased grazing intensity would benefit seed production in the source grasslands. Otherwise, landscape-wide propagule availability might increase with a more varied timing and intensity of management.
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