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1

Twiston-Davies, Grace. "Landscape connectivity : a key to effective habitat restoration in lowland agricultural landscapes". Thesis, University of Reading, 2014. http://centaur.reading.ac.uk/40659/.

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Landscape scale habitat restoration has the potential to reconnect habitats in fragmented landscapes. This study investigates landscape connectivity as a key to effective habitat restoration in lowland agricultural landscapes and applies these findings to transferable management recommendations. The study area is the Stonehenge World Heritage Site, UK, where landscape scale chalk grassland restoration has been implemented. Here, the ecological benefits of landscape restoration and the species, habitat and landscape characteristics that facilitate or impede the enhancement of biodiversity and landscape connectivity were investigated. Lepidoptera were used as indictors of restoration success and results showed restoration grasslands approaching the ecological conditions of the target chalk grassland habitat and increasing in biodiversity values within a decade. Restoration success is apparent for four species with a broad range of grass larval host plants (e.g. Melanargia galathea, Maniola jurtina) or with intermediate mobility (Polyommatus icarus). However, two species with specialist larval host plants and low mobility (Lysandra bellargus), are restricted to chalk grassland fragments. Studies of restoration grassland of different ages show that recent grassland restoration (1 or 2 years old) may reduce the functional isolation of chalk grassland fragments. A management experiment showed that mowing increases boundary following behaviour in two species of grassland Lepidoptera; Maniola jurtina and Zygaena filipendulae. Analysis of the landscape scale implications of the grassland restoration illustrates an increase in grassland habitat network size and in landscape connectivity, which is likely to benefit the majority of grassland associated Lepidoptera. Landscape and habitat variables can be managed to increase the success of restoration projects including the spatial targeting of receptor sites, vegetation structure and selection of seed source and management recommendations are provided that are transferrable to other species-rich grassland landscape scale restoration projects. Overall results show restoration success for some habitats and species within a decade. However, additional management is required to assist the re-colonisation of specialist species. Despite this, habitat restoration at the landscape scale can be an effective, long term approach to enhance butterfly biodiversity and landscape connectivity.
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Youngquist, Melissa Betty. "How Local and Landscape Factors Affect Anuran Species Distributions in Agricultural Landscapes". Miami University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=miami1437667835.

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Sutti, Flavio. "Importance Of Agricultural Systems As Multifunctional Landscapes". ScholarWorks @ UVM, 2016. http://scholarworks.uvm.edu/graddis/485.

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Agricultural landscapes provide our society with many benefits. While food production is the primary role of these landscapes, sociocultural and ecological benefits are also provided. However, the full scope of benefits that we obtain from agricultural landscapes are not always taken into account, and with the intensification of agricultural activities, more complex multifunctional landscapes are converted into simpler and less-functional landscapes. I used a heterogeneous agricultural landscape, the Champlain Valley of Vermont, as a case study to examine the interactions between landscape structure and the provision of landscape functions and services. I analyzed sociocultural and production functions indices obtained via standardized landowner surveys, and ecological function indices collected in the field for 51 plots. Plots were clustered into landscape composition categories (forest, mixed and agriculture), and configuration categories (simple and complex). I identified a tradeoff between the production and ecological function in agricultural landscapes. When a rural landscape was managed for intensive agricultural production, ecological benefits decreased. Landscapes with diversified land use/land cover and heterogeneously distributed elements returned the greatest number of benefits. Agricultural areas that comprise between 30 and 45% of the landscape can prevent the loss of ecological benefits while retaining high production. I evaluated the importance of treed habitats in agricultural landscapes in maintaining biodiversity. I related landscape metrics to ecological function indices obtained from fine-grained land use/land cover maps. Metrics obtained from fine-grained maps more accurately predicted the abundance of edge tolerant birds than those obtained from coarse grained maps. I also explored the importance of small treed landscape elements for common breeding birds and evaluated the convenience of monitoring nests comparing temperature loggers to direct observations. More heterogeneous landscapes, rich in small treed elements, supported a greater density of nests. Nests located on small treed elements in agricultural landscapes were as successful as nests located in large landscape elements. These analyses deepen our knowledge about the relationship between landscape structure and function, facilitating the evaluation of the functionality of heterogeneous agricultural landscapes.
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Sarlöv, Herlin Ingrid. "Edge habitats in agricultural landscapes : woody species, landscape ecology and implications for planning /". Alnarp : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5715-7.pdf.

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Scriven, Sarah Anne-Leigh. "Promoting resilience and biodiversity in tropical agricultural landscapes". Thesis, University of York, 2016. http://etheses.whiterose.ac.uk/17757/.

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Tropical species are facing multiple environmental pressures, whereby agricultural expansion is causing rainforest loss and climate warming is resulting in range shifts to higher elevations. In Southeast Asia, biodiversity is severely threatened by oil palm expansion and much of the remaining lowland rainforest persists within isolated fragments and protected areas (PAs). I assessed the permeability of oil palm plantations to forest dependent species by examining boundary crossing abilities of fruit-feeding butterflies. I showed that crossing was dominated by species that could potentially breed within oil palm plantations, suggesting that plantations may act as dispersal barriers to forest species. Using the PA network on Borneo as a model system, I examined the spatial distribution of climate within PAs in future, and examined the connectedness of PAs along elevation gradients. For the majority (~60-90%) of PAs, which were predominantly situated at low elevation, analogous climates in future will only be available at higher elevation, requiring species to move in order to track cooler climates. However, over half (~60-82%) of these PAs were too isolated for species with poor dispersal abilities to reach cooler, higher elevation PAs. Finally, I used a novel modelling approach based on electrical circuit theory to identify important areas of rainforest connecting PAs along elevation gradients, and showed considerable spatial overlap in expansion routes under contrasting projections of warming. Protected area extent on Borneo will need to increase by approximately one fifth (~17%) to conserve all important rainforest connections between PAs. I conclude that rainforest species may be particularly vulnerable to the impacts of continued agricultural expansion and climate change, as they may be unable to move across fragmented landscapes due to lack of connecting rainforest habitat. Management to improve linkage of PAs and ensure protection of important dispersal routes along elevation gradients should be a conservation priority.
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Prescott, Graham William. "Effects of land-use, landscape configuration, and management practice on biodiversity in tropical agricultural landscapes". Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709023.

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Ribeiro, Joana Cristina Cardoso Teixeira. "Neotropical anuran communities from agricultural landscapes: an integrated approach". Doctoral thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22247.

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Doutoramento em Biologia e Ecologia das Alterações Globais (Especialização em Ecologia e Biologia Tropical)
Anthropogenic activities such as agriculture and cattle farming are the main causes of biodiversity loss. Agricultural expansion is especially detrimental in the tropics, where agricultural investment meets important social and economic demands, and biodiversity is especially high and unique. Rice is the world’s most important food crop. Given its nature, location and extension worldwide, irrigated rice fields are invariably used by the native fauna. Determining how communities living in these agroecosystems are shaped is therefore of the utmost concern. The Cerrado, the world’s largest and most diverse savanna is experiencing extreme anthropogenic pressure, with 50% of the biome currently under direct human use. Amphibians are among the world’s most threatened vertebrates, playing keystone roles in ecosystem functioning. Given the inherent complexity of their life cycle, approaching how amphibian populations are affected by anthropogenic activities requires an integrated, multidimensional approach, at multiple scales. This project sought to assess how the anuran community of the Cerrado is being affected by agricultural pressure, assessing the extinction risk, analyzing the selected traits, and variation in taxonomic, phylogenetic and functional diversity at different scales, as well as the functional connectivity of frogs in rice crops. The official extinction risk is underestimated for the anurans of the Cerrado. Breeding site, habitat specialization, and clutch size are predictors of increased extinction risk. The southwest and central regions of the biome are the main hotspots of increased extinction risk, and should be prioritized for conservation. Habitat conversion and crop management caused profound changes to the anuran community, causing increased functional divergence and dramatic loss of functional and phylogenetic diversity in agricultural environments. Anurans with restricted range, habitat specialization, small clutches and large body size were excluded from agricultural environments. Additionally, frogs from agricultural environments had lower body condition. Thus, the conversion of natural vegetation to rice crops results in such environmental stress, that large subsets of species are driven to local extinction irrespective of their specialization, and even the more resilient species exhibit lower body condition. The presence of abundant forest fragments and water bodies is crucial for the maintenance of high levels of functional and phylogenetic diversity, and also to ensure functional connectivity for anuran populations in agricultural landscapes.
Atividades antrópicas como a agricultura e a pecuária são as principais causas da perda de biodiversidade. A expansão agrícola é especialmente nociva nos trópicos, onde o investimento agrícola responde a importantes demandas sociais e económicas, e a biodiversidade é especialmente alta e única. O arroz é a cultura alimentar mais importante do mundo. Dada a sua natureza, localização e extensão a nível global, os campos de arroz irrigado são invariavelmente utilizado pela fauna nativas. Determinar como as comunidades que vivem nesses agroecossistemas são afectadas é, portanto, de extrema importância. O Cerrado, a maior e mais diversa savana do planeta, encontra-se sob extrema pressão antropogénica, com 50% do bioma atualmente sob uso humano direto. Os anfíbios estão entre os vertebrados mais ameaçados do planeta, desempenhando papéis de destaque no funcionamento dos ecossistemas. Como o seu ciclo de vida é particularmente complexo, investigar a forma como as populações de anfíbios são afectadas por atividades antropogénicas requer uma abordagem integrada e multidimensional, a várias escalas. Com este projecto pretendeu-se avaliar a forma como a comunidade de anuros do Cerrado está a ser afetada pela pressão agrícola, avaliando o risco de extinção, analisando os traits selecionados, e a variação na diversidade taxonómica, filogenética e funcional em diferentes escalas, bem como a conectividade funcional dos anuros em culturas de arroz. Determinou-se que o risco de extinção de risco oficial dos anfíbios do Cerrado se encontra subestimado. O local de reprodução, habitat e tamanho da postura são preditores de elevado risco de extinção em anuros. O sudoeste e região central do bioma são as principais regiões de espécies de alto risco de extinção, e devem ser priorizados para a conservação. Concluiu-se também que a conversão do habitat e a gestão agrícola causaram profundas alterações na comunidade de anuros, com o aumento da divergência funcional e dramática perda de diversidade funcional e filogenética em ambientes agrícolas. Anuros com distribuição restrita, especialização de habitat, posturas pequenas e grande tamanho corporal foram excluídos dos ambientes agrícolas. Adicionalmente, anuros provenientes de culturas apresentaram menor condição corporal. Assim, a conversão de vegetação natural em plantações de arroz irrigado resulta na extinção local de muitas espécies, independentemente da sua especialização, e no decréscimo dos índices de condição corporal nas espécies mais resistentes. A presença de abundantes fragmentos florestais e de corpos de água é determinante para a manutenção de níveis elevados de diversidade funcional e filogenética, e ainda para assegurar a conectividade funcional para as populações de anuros em paisagens agrícolas.
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Job, Nancy, i William Ellery. "Halting degradation of Southern Cape peatlands in agricultural landscapes". Rhodes University, 2013. http://hdl.handle.net/10962/50013.

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Palmiet peatlands in the agricultural landscape are viewed by farmers as problematic. They obstruct the effective passage of water along watercourses and therefore promote localized flooding of lands and infrastructure, and they trap sediment delivered along watercourses that drowns fields and infrastructure with sedimentary deposits. These events are problematic for farmers trying to make a living off the land. Wetlands are also often viewed as wastelands that should be put to more productive use. The obvious thing to do is to bring in machinery to drain the wetlands and improve the flow of water and sediment through these wetlands.
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Gemesi, Zsolt. "Plumbing agricultural landscapes for water quality improvement coexistence of intensive agriculture and good water quality /". [Ames, Iowa : Iowa State University], 2007.

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Thiesen, Thais H. Ms. "A Framework for assessing Alternative Agro-Ecosystems: finding Multi-Functional Solutions for Sustainable urban landscapes". FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/3042.

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Creating sustainable urban landscapes in light of growing population pressures requires interdisciplinary multi-functional solutions. Alternative agro-ecosystems described as food forests, permaculture gardens, and/or edible landscapes among others could offer potential ways to address the social, economic and ecological goals of various stakeholders simultaneously. The present research used a unique rubric, the Permaculture and Agro-ecosystems Sustainability Scorecard (PASS) that combines existing agricultural and landscape sustainability indicators in order to assess alternative agro-ecosystems. The rubric evaluates provisioning, regulating, supporting and cultural ecosystem services such as pollinator presence, biodiversity, pesticides and fertilizer use, carbon sequestration and human interactions. The PASS was used to score twelve sites in South Florida that meet specific criteria in the small farm, residential and public space categories. The results showed that the majority of the sites scored highest in the supporting services provided, followed by regulating and cultural services and lowest in the economic services category.
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Okey, Brian W. "Toward agroecosystem health, assessment of biodiversity in contrasting agricultural landscapes". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ35808.pdf.

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Kinkaid, Eden. "The architecture of ecology: Systems design for sustainable agricultural landscapes". Ohio University Honors Tutorial College / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ouhonors1366983104.

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Cutright-Smith, Elisabeth. "Modeling Ancestral Hopi Agricultural Landscapes: Applying Ethnography to Archaeological Interpretations". Thesis, The University of Arizona, 2007. http://hdl.handle.net/10150/193274.

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In this thesis, historic Hopi ethnographic data are employed to model ancestral Hopi agricultural land use through the lens of archaeological landscape theory. Emphasizing the interconnectedness of landmarks--loci of discrete interactions between humans and the land--within networked cultural landscapes, archaeological landscape theory provides a unique perspective from which to examine overlapping planes of historic and prehistoric land use.Drawing on ethnographic accounts, a model is constructed that integrates the physical, social organizational, ritual/ceremonial, and traditional history dimensions of historic Hopi agricultural land use. Durable material correlates of agricultural land use are proposed on the basis of ethnographic documentation. This holistic model is applied to archaeological data from the Homol'ovi Ruins State Park (HRSP), northeastern Arizona. The integrative model produced herein allows for the interpretation of relationships between archaeological features representing different land use behaviors and the conceptualization of linkages between landmarks in the ancestral Hopi agricultural landscape.
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Roos, Bonnie. "Balancing Agricultural and Urban Water Needs in Transitioning Arid Landscapes". DigitalCommons@USU, 2016. https://digitalcommons.usu.edu/etd/5017.

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In the arid western United States (U.S.), population expansion is dependent on water supply. With the majority of the water being consumed in agriculture, municipalities often obtain water supply needed for growth from agriculture. Water supply reallocation generally occurs through agricultural-to-urban water right transfers. This trend in agricultural-to-urban water transfers drives the question of how to strike a balance between agricultural and urban water needs in rapidly growing arid regions. In the Intermountain West region of the United States, Utah is a state with a rapidly growing population and limited water supply. This study occurred between 2015 and 2016, using a multi-method approach to understand agricultural-to-urban water transfers in Utah. Inperson interviews, participant observation, and secondary data collection methods focused on existing challenges and opportunities for striking a balance between these water interests. Data revealed that water transfers out of agriculture and into municipalities are more significant to areas of Utah experiencing rapid population growth. Policy challenges arise as water is seen as a monetary asset, incentivizing the reintroduction of old water rights into an established water priority system. Further challenges occur as municipal uses are given preference in state development strategies over agricultural uses. This preference can incentivize both the selling of water to municipalities and the gathering of large municipal water right portfolios. Balancing growth and water interests in transitioning landscapes is suggested through the use of agreements, as well as regional planning and collaboration. This transition, if not properly planned and accounted for in the water budget, can create dilemmas with water availability, delivery, and use as separate water providers prepare for growth within their own geographic boundaries. The Mt. Nebo Water Agency provides the opportunity for stakeholder involvement and boundary-spanning to occur between regional municipal and agricultural interests. Stakeholder involvement and boundary-spanning solutions are considered crucial factors for regional planning, particularly with resources like water that traverse political boundaries.
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Zivec, Peta L. "Natural regeneration of floodplain vegetation in semi-arid agricultural landscapes". Thesis, Griffith University, 2022. http://hdl.handle.net/10072/413993.

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Few areas on earth remain untouched by human activity. Agricultural land has become the largest terrestrial biome globally with ~ 40% of earth’s surface occupied by pastures and croplands. This has resulted in widespread biodiversity loss and ecosystem alteration, which is being further exacerbated by climate change. Urgent and widespread revegetation of agricultural landscapes is required to slow and remediate these impacts. Simultaneously, the extent of abandoned agricultural land, often referred to as old-fields, is increasing worldwide due to a range of socioeconomic factors, providing significant opportunities for revegetation. Natural regeneration, whereby an area is left to revegetate on its own, with minimal human intervention, can be a cost-effective and large-scale restoration approach well suited to some, but not all, agricultural landscapes. While there are numerous success stories regarding natural regeneration from around the world, natural regeneration in other areas is significantly constrained by low propagule supply and/or high levels of land degradation. Considerable knowledge gaps regarding patterns and drivers of natural regeneration remain and improved understanding of these processes is critical for informing improved decisions regarding effective revegetation strategies for degraded landscapes. This thesis examines natural regeneration of vegetation within agricultural landscapes, specifically of old-fields, with a focus on floodplains of the northern Murray-Darling Basin, Australia. More specifically, the research presented here sought to: 1) understand global trends of natural regeneration of woody vegetation in agricultural landscapes and its key drivers,; 2) describe patterns and drivers of natural regeneration within floodplain old-fields of the northern Murray-Darling Basin; 3) understand the regenerative capacity from major propagule sources within agricultural floodplain landscapes of the northern Murray-Darling Basin; and 4) investigate how different hydrological events influence the regeneration of riparian vegetation in semi-arid agricultural landscapes. Chapter 1 introduces the thesis, presenting background information on revegetation within agricultural landscapes, restoration approaches, a conceptualisation of states and trajectories of natural regeneration, and a description of the study area. In Chapter 2, I explore the global literature on natural regeneration within agricultural landscapes through a systematic quantitative literature review designed to provide a deeper understanding of the compositional and structural characteristics of naturally regenerating woody vegetation, key factors driving these patterns, and the global state of knowledge in this field. To conduct this review, I surveyed an initial 947 research papers from across the globe and selected a shortlist of 84 primary empirical studies based on a set of inclusion and exclusion criteria. Among the shortlisted studies, it was observed that regenerating vegetation does not return completely to that of remnant reference conditions in relation to composition and structural characteristics, and most commonly exhibits novel attributes in relation to both. Land-use history, propagule supply, species interactions (i.e., facilitation and competition), and soil properties emerged as the four broad factors driving patterns in naturally regenerating woody vegetation in oldfields globally. Overall, the review found that despite vegetation regrowing with a novel compositional and structural character, this approach does provide a viable form of restoration in a wide range of conditions. In Chapters 3, 4, and 5, the results are then presented of several field and glasshouse studies designed to better understand patterns, processes, and drivers of natural regeneration in floodplain old-fields across the northern Murray-Darling Basin. Chapter 3 explores patterns and drivers of extant woody vegetation regrowth on old-fields distributed amongst four major regions representing a broad aridity gradient across the northern Murray-Darling Basin. The aim of this chapter is to identify key compositional and structural characteristics of naturally regenerating woody vegetation, and drivers of these, across the study area. This study found that after approximately 30–40 years, woody vegetation in these old-fields begins to regenerate in greater density to that of remnant reference sites. Nevertheless, regenerating old-fields did support woody vegetation of similar species composition to remnant reference sites. Mean annual rainfall, time since abandonment, and presence of remnant paddock trees were identified as major drivers of natural regeneration in this study. Overall, this chapter demonstrates that natural regeneration can be a viable form of restoration within these landscapes, provided adequate time for recovery is allowed. For successful natural regeneration to occur, there must be adequate plant propagules within a site and/or being supplied to the area. Chapter 4 explores how various major seed banks (i.e., soil, animal scat and leaf litter) contribute to the overall regenerative capacity of old-fields in the northern Murray-Darling Basin. The year-long seedling emergence experiment studied seed banks from the 12 old-fields as well as adjacent remnant vegetation patches investigated in Chapter 3, to understand how land-use history influences regenerative capacity. This study found that each seed bank type played an important role in contributing to the overall regenerative success, although, there was little difference between seed banks of different land-use histories, indicating high levels of seed bank resilience to agricultural land-use disturbances. The results suggest that soil seed banks are vital for storing high herb species richness. Additionally, animal scats support relatively high abundances of emerging seedlings, indicating that zoochory is likely to be a vital seed dispersal mode within these landscapes. Finally, leaf litter, while producing very low abundances of emerging seedlings overall, contained the highest abundance of germinable seeds of woody species in these oldfields. Very low numbers of woody tree seedlings emerged from the experiment overall, however, indicating that trees are unlikely to store seeds within these seed banks in these habitats and likely rely on more immediate supply from remnant paddock trees or vegetation patches. This research indicated that seed banks are important contributors to natural regeneration of these old-fields, but mainly with respect to understory and midstory species. Within semi-arid ecosystems, water regimes are critical in driving plant establishment and vegetation regeneration and previous research has shown the importance of flooding in shaping plant population and vegetation dynamics within arid and semi-arid floodplain habitats. Knowledge gaps remain, however, regarding the importance of flooding versus rainfall events. In this chapter, I present the results of a field experiment examining the establishment of Eucalyptus camaldulensis seedlings and understory vegetation in response to differing hydrological events (flooding, rainfall and drought) in two different habitat types (remnant riparian zone and adjacent floodplain old-field). Imposed flooding, rainfall and drought treatments were conducted on 180 Eucalyptus camaldulensis and in situ extant vegetation within 18 grazing enclosure plots over a 9-month experiment. Overall, there was very high seedling mortality, with ~3% of Eucalyptus seedlings surviving the entire experiment. Flooding was critical, however, in driving this survival of seedlings and supporting the resilience of understory cover and diversity over this period. The survival of seedlings up until 10 weeks was higher in riparian plots than in floodplain old-field plots, although habitat type had less of an effect within flooded plots. The results of this study demonstrates that rainfall alone is unlikely to be sufficient to enable adequate vegetation regeneration in these habitats. Overall, the combined results of this project clearly demonstrate that floodplain old-fields of the northern Murray-Darling Basin exhibit significant resilience to previous agricultural landuse at landscape scales. Furthermore, this thesis demonstrates that natural regeneration is a viable approach to revegetating old-field floodplain habitats in this region, adding to the broad range of diverse case studies reporting effective natural regeneration in agricultural landscapes globally. The final chapter (Chapter 6) of this thesis synthesises the key findings and management implications of the knowledge generated by this thesis, as well as identifying future research needs which can better support effective regeneration strategies of such landscapes.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
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Haslem, Angie, i angie haslem@deakin edu au. "Landscape Pattern, Countryside Heterogeneity and Bird Conservation in Agricultural Environments". Deakin University. Life and Environmental Sciences, 2008. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20090114.101341.

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Agricultural environments are critical to the conservation of biota throughout the world. This is due both to the limited extent of current reserve systems and the large, and still expanding, proportion of terrestrial environments already dominated by agricultural land-uses. Consequently, there is a growing call from scientists around the world for the need to maximise the conservation value of agricultural environments. Efforts to identify key influences on the conservation status of fauna in agricultural landscapes have taken complementary approaches. Many studies have focussed on the role of remnant or semi-natural vegetation, and emphasised the influence on biota of spatial patterns in the landscape. Others have recognised that many species use diverse ‘countryside’ elements (matrix habitats) within farmland, and emphasise the benefits of landscape heterogeneity for conservation. Here, these research themes have been combined. This study takes a whole-of-landscape approach to investigating how landscape pattern and countryside heterogeneity influence the occurrence of birds in agricultural environments. Birds were sampled in 27 agricultural mosaics, each 1 km x 1 km in size (100 ha), in Gippsland, south-eastern Australia. Mosaics were selected to incorporate variation in two landscape properties: the cover of native vegetation, and richness of different types of element (i.e. land-uses/vegetation types). In each mosaic, 15 fixed sampling locations were stratified among seven different elements in proportion to their cover in the mosaic: native vegetation, linear vegetation, tree plantation, scattered paddock trees, pasture, wetlands and farm dams. Six point counts of birds were undertaken at all sample points in each mosaic: three each in the breeding and non-breeding months of a one-year period (October 2004 – August 2005). Independent measures of the composition, configuration, and heterogeneity of elements in the mosaic had differing effects on the richness of bird species recorded in these same mosaics. Sub-groups of birds based on habitat requirements responded most strongly to the extent of preferred element types in mosaics. Woodland birds (those of greatest conservation concern in farmland environments in Australia) were richer in mosaics with higher cover of native vegetation while open-tolerant species responded to the extent of scattered trees. In contrast, for total species richness, mosaic heterogeneity (richness of element types) and landscape context (cover of native vegetation in surrounding area) had the greatest influence. Mosaic structural properties also influenced the composition of entire bird assemblages in study mosaics. Avifaunal composition showed systematic variation along two main gradients which were readily interpreted in relation to landscape properties: 1) a gradient in the cover of wooded vegetation and, 2) the proportional composition of vegetation types in the mosaic. These gradients represent common trajectories of landscape modification associated with agricultural development: namely, the removal of wooded vegetation and the replacement of native species with exotic vegetation (e.g. crops and plantations). Species possessing different characteristics in relation to three avian life-history traits (nest type, feeding guild and clutch size) varied significantly in their position along these gradients of landscape modification. Species with different nesting requirements showed a strong relationship with the gradient in wooded vegetation cover while species belonging to different feeding guilds were influenced by the gradient defined by the replacement of native vegetation with exotic species. More bird species were recorded in native vegetation than in any other type of element sampled in this study. Nevertheless, most countryside elements had value for many species; particularly structurally complex elements such as scattered trees and tree plantation. Further, each type of landscape element contained different bird assemblages. Species that were recorded in a greater number of different types of landscape element were also recorded in more mosaics. This was true for all species and for woodland birds, and indicates that species that can use a greater range of countryside elements may have an increased tolerance of future landscape modification. The richness of woodland species at survey sites in different elements was influenced by features of the mosaic in which they occurred. Notably, the richness of woodland bird species recorded at sites in scattered trees and pasture increased with a greater cover of native vegetation in the overall mosaic. Of the overall pool of woodland bird species documented in the broader study region, 35% of species were not recorded in the agricultural mosaics sampled here. While many of these species were uncommon in the study area, or were associated with vegetation communities infrequently sampled in mosaics, this shows that conservation efforts in agricultural landscapes will not be appropriate for all species. For those woodland species that were recorded, measures of the extent of wooded vegetation cover had a strong, positive influence on the frequency of occurrence of individual species in mosaics. Thus, individual species of woodland bird occurred more frequently in mosaics with a greater cover of wooded vegetation. Nine woodland species showed a stronger response to measures of vegetation cover that included tree plantation and/or scattered trees than to the cover of native vegetation alone. For these species, structurally complex countryside elements provide valuable supplementary habitat at the landscape scale. Results of this study show that landscape properties influence the occurrence of birds in agricultural mosaics. The extent of cover of element types, particularly native vegetation, had the strongest influence on all measures of bird occurrence in mosaics. Thus, native vegetation is vital for the persistence of birds in farmland landscapes and is the primary element on which conservation efforts in these environments depend. Nevertheless, with careful management, countryside elements may provide additional conservation benefits for many bird species. Countryside elements made an important contribution to landscape heterogeneity, the landscape property with greatest influence on overall bird richness in mosaics. Countryside elements also increased the structural complexity of cleared agricultural land, and so have the capacity to enhance connectivity in fragmented landscapes. A focus on these factors (landscape heterogeneity and structural complexity) will provide the greatest opportunities for using countryside elements to increase the conservation value of farmland environments for native fauna. The relatively small scale of this study indicates that the cumulative effect of even small elements in farm mosaics contributes to the structural properties of entire landscapes. Critically, this emphasises the important contribution that individual landholders can make to nature conservation in agricultural environments.
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Cesar, Ricardo Gomes. "Local and landscape drivers of tropical forest regeneration in agricultural landscapes of the Atlantic Forest of Brazil". Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-16072018-173459/.

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Forests established through native seedling planting (PL) and the establishment of secondary forests through natural regeneration (SF) are the main outcomes of large scale forest restoration. The decision making process of these approaches is conditioned by resilience. But the different outcomes of these approaches are as important as the decision making. SF are heterogeneous and - although there is a growing literature of the drivers of forest establishment - few works analyzed drivers of attributes of these recently established forests. In this context, our work aims to identify the differences between PL and SF and the local and landscape variables that affect SF attributes. To do so, we sampled the tree community in seasonal semideciduous forests of the Atlantic Forest established naturally (SF) and PL in agricultural landscapes in the Corumbataí Watershed, São Paulo State, Brazil. We observed that PL has similar biomass to SF and higher species richness. However, PL also showed lower abundance of young trees, animal-dispersed trees and lianas. Species composition between PL and SF also differs. SF established in abandoned eucalypt plantings showed species richness and biomass of native species similar to other SF forests. However, SF attributes vary greatly. In this context, SF show a large potential for providing food for fauna and storing carbon in a cost-efficient way. While PL can also provide these benefits, it may have its long-term sustainability compromised by the lack of regenerating trees. We then proceeded to investigate drivers of the heterogeneity observed in SF using generalized linear mixed models to estimate the effect of local and landscape variables on the biomass, species density and basal area of animal-dispersed trees of the SF sampled. SF surrounded by sugarcane plantations had lower biomass and basal area of animal-dispersed trees, while native forest cover in the landscape increased species density of SF. Forest age showed little or no importance in predicting SF attributes. These results highlight the importance of low impact agricultural practices and of strategies that increase native forest cover in agricultural landscapes, in order to increase the potential of SF to provide ecosystem services and conserve taxonomic diversity. The choice between establishing PL or fomenting SF for forest restoration is conditioned to the local and landscape context where restoration actions will be carried out. Although both approaches can potentially fulfill the objectives of restoration projects, special attention must be given to the recruitment of new individuals to maintain PL sustainability, while less impacting agricultural practices and more forested agricultural landscapes may increase the SF potential to provide ecosystem services and conserve biodiversity.
Florestas estabelecidas pelo plantio de mudas de espécies nativas (PL) e por meio do estabelecimento de florestas secundárias pela regeneração natural (FS) são as principais comunidades geradas durante a restauração florestal em larga escala. A escolha dessas estratégias está condicionada potencial de regeneração natural do local, mas tão importante quanto a decisão sobre métodos de restauração, são as diferenças das comunidades que essas escolhas podem gerar. As FS são heterogêneas e, enquanto existe uma literatura crescente dos fatores que afetam a chance do estabelecimento das FS, poucos trabalhos abordam os fatores que influenciam os atributos dessas florestas. Nesse contexto, nosso trabalho busca identificar as diferenças entre PL e FS e as variáveis locais e de paisagem que afetam os atributos das FS. Para tal, amostramos a comunidade arbórea de florestas estacionais semideciduais de Mata Atlântica estabelecidas naturalmente (FS) e por PL em paisagens agrícolas na bacia do Rio Corumbataí, no estado de São Paulo. Observamos que os PL apresentam biomassa semelhante às SF e maior riqueza de espécies. No entanto, as PL também apresentam menor abundância de indivíduos jovens, indivíduos zoocóricos e lianas. A composição de espécies entre essas florestas também difere. As FS estabelecidas em plantios abandonados de eucalipto apresentaram riqueza de espécies e biomassa de espécies nativas semelhantes a outras florestas secundárias. No entanto, os atributos das SF variam consideravelmente. Nesse contexto, as FS apresentam elevado potencial de provimento de alimento para a fauna e estocagem de carbono de maneira custo-eficiente, enquanto que as PL podem ter sua permanência em longo prazo comprometida pela falta de indivíduos jovens. Em seguida, investigamos as variáveis que direcionam a heterogeneidade observada nas FS utilizando modelos mistos lineares generalizados para estimar a influência de variáveis locais e de paisagem na biomassa, densidade de espécies, área basal de árvores zoocóricas e estrutura filogenética das FS amostradas. Plantios de cana-de-açúcar próximos as FS reduzem a biomassa e área basal de indivíduos zoocóricos, enquanto que a cobertura florestal da paisagem aumentou a densidade de espécies e a diversidade filogenética. A idade da floresta apresentou importância secundária ou nula para os atributos estudados. Nossos resultados ressaltam a importância de práticas agrícolas que minimizem os danos em florestas próximas e de mecanismos que favoreçam a cobertura florestal nativa em paisagens agrícolas, a fim de fomentar o potencial dessas florestas em prover serviços ecossistêmicos e conservar a biodiversidade. A escolha entre facilitação do estabelecimento de FS ou PL visando a restauração florestal está condicionada ao contexto local e de paisagem onde serão realizadas as ações de restauração. Apesar de ambas as abordagens apresentarem potencial para cumprir os objetivos dos projetos de restauração, atenção especial deve ser dada ao recrutamento de novos indivíduos para manter a sustentabilidade de PL, enquanto que práticas agrícolas menos impactantes e paisagens agrícolas com maior cobertura florestal nativa podem aumentar o potencial de SF em prover serviços e conservar a biodiversidade.
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Castellazzi, M. S. "Spatio-temporal modelling of crop co-existence in European agricultural landscapes". Thesis, Cranfield University, 2007. http://dspace.lib.cranfield.ac.uk/handle/1826/3747.

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The environmental risk of growing genetically modified (GM) crops and particularly the spreading of GM genes to related non-GM crops is currently a concern in European agriculture. Because the risks of contamination are linked to the spatial and temporal arrangements of crops within the landscape, scenarios of crop arrangement are required to investigate the risks and potential coexistence measures. However, until recently, only manual methods were available to create scenarios. This thesis aims to provide a flexible referenced tool to create such scenarios. The model, called LandSFACTS, is a scientific research tool which allocates crops into fields, to meet user-defined crop spatio-temporal arrangements, using an empirical and statistical approach. The control of the crop arrangements is divided into two main sections: (i) the temporal arrangement of crops: encompassing crop rotations as transition matrices (specifically-developed methodology), temporal constraints (return period of crops, forbidden crop sequences), initial crops in fields regulated by temporal patterns (specifically-developed statistical analyses) and yearly crop proportions; and (ii) the spatial arrangements of crops: encompassing possible crops in fields, crop rotation in fields regulated by spatial patterns (specifically-developed statistical analyses), and spatial constraints (separation distances between crops). The limitations imposed by the model include the size of the smallest spatial and temporal unit: only one crop is allocated per field and per year. The model has been designed to be used by researchers with agronomic knowledge of the landscape. An assessment of the model did not lead to the detection of any significant flaws and therefore the model is considered valid for the stated specifications. Following this evaluation, the model is being used to fill incomplete datasets, build up and compare scenarios of crop allocations. Within the GM coexistence context, the model could provide useful support to investigate the impact of crop arrangement and potential coexistence measures on the risk of GM contamination of crops. More informed advice could therefore be provided to decision makers on the feasibility and efficiency of coexistence measures for GM cultivation.
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Schriever, Carola Alexandra. "Modeling ecological risk of runoff for benthic invertebrates in agricultural landscapes /". Leipzig : UFZ, 2007. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=015694027&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Goss, Charles W. "Influence of forest fragments on headwater stream ecosystems in agricultural landscapes". The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1387536064.

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21

Villard, Marc-Andre Carleton University Dissertation Biology. "Spatio-temporal dynamics of forest bird patch populations in agricultural landscapes". Ottawa, 1991.

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Nicholson, Charles C. "No Farm Is An Island: Pollinators And Pollination In Agricultural Landscapes". ScholarWorks @ UVM, 2018. https://scholarworks.uvm.edu/graddis/985.

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Productive, resilient and sustainable agricultural systems are required to meet the immediate needs of a burgeoning human population, while avoiding ecosystem collapse. Agriculture provides food, fiber, fuels and other products for our current population of 7 billion and is still the major livelihood for 40% of people worldwide. By replacing natural habitat and employing chemical inputs, agriculture also negatively impacts biodiversity and impairs the provision of ecosystem services. This poses a challenge for agriculture as these impacted services are often those required for high yielding and high-quality crop production. Evidence is accumulating that agricultural management can safeguard biodiversity and ecosystem services while maintaining production, but critical questions remain concerning how management actions are shaped by broader landscape pattern and how these actions influence service-providing organisms across space and time. Through a combination of observational, experimental and modeling approaches, my dissertation examines relationships between management actions, landscape pattern and service-providing organisms using crop pollination by wild bees as a model system. First, I investigate how local management and landscape pattern interact to affect pollination services and the abundance and diversity of native bees in Vermont, USA. I then use two established models of pollinator foraging to investigate whether one popular intervention, enhancing floral resources, improves crop visitation, and whether pollinator traits and landscape pattern influence this effect. Next, I use a national data set of native bee diversity to test whether habitat enhancements increase taxonomic and functional diversity of native bee communities. Finally, I investigate whether resource continuity provided by consecutively blooming crops benefits wild bee communities. These four chapters contribute ecological knowledge of plant-animal interactions in anthropogenic landscapes. My findings also provide land managers with clear information about the effects of landscape conservation and farm management on crop pollinators.
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Fischer, Joern. "Beyond fragmentation : lizard distribution patterns in two production landscapes and their implications for conceptual landscape models /". View thesis entry in Australian Digital Theses Program, 2004. http://thesis.anu.edu.au/public/adt-ANU20060718.150101/index.html.

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Sheppard, Rebecca Jean. "Making the farm pay persistence and adaptation in the evolution of Delaware's agricultural landscape, 1780-2005 /". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 536 p, 2009. http://proquest.umi.com/pqdweb?did=1825749021&sid=4&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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25

Solé-Senan, Xavier Oriol. "Plant diversity and ecosystem services in agricultural landscapes along different spatial scales". Doctoral thesis, Universitat de Lleida, 2017. http://hdl.handle.net/10803/406287.

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Aquesta tesi té com a objectiu escatir fins quin punt les diversitats d'espècies i funcional de les comunitats de flora arvense canvien a escala de camp i de paisatge. A escala de camp, l'estudi s'ha focalitzat en l'anàlisi de l'efecte de la intensificació agrícola, depenent de la posició dins del camp i en funció del nivell de pertorbació en cada hàbitat que forma part del tradicional paisatge en mosaic en els ambients mediterranis. A escala de paisatge, hem analitzat els canvis en la diversitat al llarg de gradients d'heterogeneïtat en el paisatge, tenint en compte d'una banda l'heterogeneïtat composicional i per l'altra l'heterogeneïtat configuracional. L'aproximació basada en atributs biològics ens ha permès dirigir l'estudi a analitzar de quina manera afecten els canvis a la composició florística d'aquestes comunitats a la provisió dels serveis ecosistèmics que els agroecosistemes aporten a altres organismes.
La presente tesis tiene como objetivo dilucidar hasta qué punto la riqueza en especies y la diversidad funcional de las comunidades de flora arvense cambian a escala de campo y de paisaje. A escala de campo, el estudio se ha enfocado en el análisis del efecto de la intensificación agrícola, en cuanto a la posición en el campo y al nivel de perturbación en cada hábitat en la diversidad y funcionalidad de las comunidades de flora arvense. A escala de paisaje, hemos analizado los cambios en la diversidad a lo largo de gradientes de heterogeneidad en el paisaje, teniendo en cuenta por un lado la heterogeneidad composicional y por el otro la heterogeneidad configuracional. La aproximación basada en atributos biológicos nos ha permitido enfocar el estudio en cómo afectan los cambios en la composición florística de dichas comunidades a la provisión de los servicios ecosistémicos que los agroecosistemas aportan a otros organismos.
This thesis is aimed at disentangling the extent at which species richness and functional diversity of plant species from arable communities change at field and landscape scale. At field scale, the study was focused on the effects of agricultural intensification regarding field position and the level of disturbance at which such habitat is subjected on the diversity and functionality of arable plants community. At landscape scale, we assessed the diversity changes along gradients of landscape heterogeneity, taking into account on the one hand the surrounding compositional landscape heterogeneity and on the other hand the configurational landscape heterogeneity. The trait-based approach conducted allows us to focus on how shifts in species composition in such arable plant communities are expected to affect the delivery of the ecosystem services that these agroecosystems provide to other organisms.
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26

Larsson, Jimmie. "Traditional agricultural landscapes and their importance in the fight against land degradation". Thesis, Högskolan i Halmstad, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-43201.

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Markförstöring är idag ett utbrett problem som till stor del är orsakat av konventionellt jordbruk och ohållbar markanvändning. Traditionella jordbrukslandskap har i många områden bedrivits under lång tid utan att uppvisa samma problem samtidigt som de haft hög artmångfald. Denna litteraturstudie studerar dessa landskap med inriktning på Europa och Ostasien. Resultatet visar att det är flera faktorer som är viktiga i deras bevarande av artmångfald såsom heterogenitet, konnektivitet och intermediära störningar. Utöver detta så är effektiv återvinning av näringsämnen, användning av poly-kulturer och jordbrukslandskapens låga intensitet, viktiga faktorer som skyddat dem från överexploatering. Problemet med traditionella jordbrukslandskap är att de inte är ekonomiskt hållbara. Även om restaurering av ekosystem är ett av FN:s mål det kommande decenniet så sker det inte om det inte finns ett incitament att restaurera. Genom att bättre förstå hållbara jordbrukslandskap kan vi i framtiden skapa både ekologiskt resilienta och ekonomiskt stabila produktionslandskap som inte bara gynnar samhället utan även artmångfalden.
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Mills-Novoa, Megan, i Megan Mills-Novoa. "Understanding Water Policy as Agricultural Policy: How IWRM Reform is Reshaping Agricultural Landscapes under Climate Change in Piura, Peru". Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/621847.

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One billion people currently live in basins that are likely to require action to address climate change-induced water stress. Rather than blaming dwindling resource availability as the key culprit for this global water crisis, the United Nations has dubbed the water crisis a "crisis in governance." One of the key prescriptions promoted by multilateral funders and international water experts for addressing the looming crisis has been water policy reform that follows the principles of Integrated Water Resource Management (IWRM). While there has been significant research on the IWRM model, few people have conducted empirical studies that examine how IWRM water reform generates changes within the agricultural sector. It is particularly important to study the tight coupling of agricultural and water policy in light of a changing climate, which poses substantial challenges to water availability and agricultural production. In this thesis, I explore the salient case study of the Piura River Basin in northern Peru. I employ semi-structured interviews with key institutional actors in the agricultural and water sector, participant observation, and technical document review to examine how the IWRM-based 2009 Water Resources Law is reshaping agricultural land use under climate change and globalization pressures. I argue that 2009 Water Resources Law formalized and limited public participation within the newly formed river basin council, while concurrently strengthening technocratic water allocation institutions that limit the agency of smallholder water users to make agricultural land use decisions. Additionally, I find that climate change adaptation discourse is being operationalized within river basin council to legitimize these reforms, but these reforms are explicitly enrolled in agricultural development policy aimed at converting traditional agricultural systems to export-oriented production. This study contributes to the fledgling scholarship on the implications of the 2009 Water Resource Law for Peruvian agricultural communities. More broadly, my findings offer insight into how IWRM reshapes the agricultural sector, how this is situated into the continually shifting role of the state, and how these policy reforms integrate and animate climate change adaptation.
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Roy, Valérie 1981. "The ecological value of hedgerows for conserving temperate forest herbs in agricultural landscapes /". Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=111932.

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There is growing evidence that the achievement of biodiversity conservation objectives at the regional scale will have to take into account not only habitats within reserves, but also the contribution of semi-natural habitats in production landscapes. This requires knowledge of the conditions that maintain or enhance biodiversity in these suboptimal habitats. I focused on a system of forest patches and hedgerows in an agricultural landscape as habitats for dispersal-limited native forest herbs to (1) identify species-specific traits that appear to either limit or facilitate survival or colonization of forest herbs in hedgerows compared to forest patches, and (2) to evaluate the relative contribution of landscape and local variables in explaining patterns of forest herb species richness, abundance, and diversity in hedgerows. A fourth-corner analysis revealed that traits such as early spring flowering, ant dispersal or a lack of vegetative propagation can reduce the likelihood of native forest species to benefit from hedgerows. Conditional autoregressive models showed that landscape variables, specifically hedgerow age and neighboring forest area, largely account for species diversity in hedgerows.
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Brühl, Carsten [Verfasser], i Ralf [Gutachter] Schulz. "Agricultural landscapes, their biodiversity and impacts of pesticides / Carsten Brühl ; Gutachter: Ralf Schulz". Landau : Universität Koblenz-Landau, Campus Landau, 2019. http://d-nb.info/1197612769/34.

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Howlett, C. E. "Agricultural development and the re-formed rural landscapes of Kincardineshire c1750 to 1880". Thesis, University of Aberdeen, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234038.

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Changes in the agriculture of Kincardineshire between c.1750 c.1880 were fundamental and produced great variety in the rural landscape. A few famous Improvers introduced new crops and agricultural techniques in the 1750s and 1760s, but general adoption was not possible until the late eighteenth and early nineteenth centuries, when a more highly developed transport and marketing system allowed smaller landowners and tenant-farmers to accumulate capital. Several important introductions of crops, crop rotations and types of livestock did not take place until the early nineteenth century. Following a brief lull during the post-Napoleonic War economic depression, rapid development began again in the in the 1820s and 1830s, culminating in a boom period after the coming of the railway in 1850, involving cattle fattening, artificial fertilizers and draining. Many of the early changes in landscapes were mainly restricted to the environmentally favoured south of the country. It was here that wasteland reclamation was taking place towards the end of the eighteenth century, so that by the early nineteenth century the arable area had reached its greatest extent. At the same time the impermanent pre-improvement farm buildings began to be adapted and extended, and were eventually replaced by durable stone steadings. Only in enclosure did the south lag behind the north of the country. Re-formation of the landscape in the north, particularly in western Deeside, did not advance rapidly until the second phase of activity beginning in the 1820s and 1830s. Most of the dry-stone wall building occurred in the half century to 1880, as did the development of the farm steadings. The arable area expanded very rapidly during the nineteenth century. Changes in agriculture and landscapes in Kincardineshire c.1750 to c.1880 exhibit both revolutionary and evolutionary characteristics.
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Brühl, Carsten A. [Verfasser], i Ralf [Gutachter] Schulz. "Agricultural landscapes, their biodiversity and impacts of pesticides / Carsten Brühl ; Gutachter: Ralf Schulz". Landau : Universität Koblenz-Landau, Campus Landau, 2019. http://nbn-resolving.de/urn:nbn:de:kola-19677.

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32

Shackelford, Gorm. "Biodiversity and ecosystem services : pollination, biological control, and nature conservation in agricultural landscapes". Thesis, University of Leeds, 2014. http://etheses.whiterose.ac.uk/7411/.

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Agriculture has done more damage to nature than any other human activity, and yet food production could need to be doubled by the middle of this century. As agricultural land is expanded and intensified, critical thresholds in the loss of natural habitats are crossed. This loss of non-crop habitats can have negative feedback on crop production, because it can cause a loss of “ecosystem services” that support and regulate crop production, such as the pollination of crops by bees and the biological control of crop pests by their natural enemies. Because of this connection between non-crop habitats and crop yields, there could be potential for habitat conservation to benefit both agriculture and nature. The research in this thesis focuses on pollinators and natural enemies, because these species constitute a vital connection between food production and biodiversity conservation. Could habitat management be used to conserve both pollinators and natural enemies in agricultural landscapes? Will the relationships between pollinators, natural enemies, and natural habitats change with climate change? Where should we prioritize the resolution of conflict between agriculture and nature, and how? This thesis addresses these questions through literature review and meta-analysis, geographic information systems (GIS) and hotspot analysis, field research on the distributions of trap-nesting bees and wasps on environmental gradients, and laboratory research on the development of bees and wasps at high temperatures. This thesis suggests that it might be possible to conserve communities of both pollinators and natural enemies, in general, by means of habitat management, but it might not be possible to conserve specific combinations of pollinators and natural enemies, which might have opposite responses to some forms of environmental change, such as global warming. This thesis also suggests that the resolution of conflict between agriculture and nature should be prioritized in sub-Saharan Africa, and it outlines a conceptual framework for systematic conservation planning in agricultural landscapes.
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33

Prior, Kara. "In-stream nitrogen processing and dilution in an agricultural stream network". Thesis, University of Iowa, 2015. https://ir.uiowa.edu/etd/1729.

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The interaction of agricultural fertilizer application and a drought-to-flood transition in 2012-2013 set up conditions for a watershed-scale experiment on nutrient dynamics. The region-wide drought in 2012 left surface soils disconnected from stream networks and restricted nutrient use by crops, resulting in an unusually large nitrogen pool stored in the soil column through the winter. The wet conditions in the Midwest in spring of 2013 mobilized the unused fertilizer from the landscape into the stream network. A six-week period of extremely high in-stream nutrient concentrations followed. This study analyzes results of three synoptic sampling campaigns in the Iowa-Cedar River Basin in 2013 to quantify patterns in nitrogen dynamics. I estimate nutrient spiraling metrics by interpreting the fertilizer mobilization from the landscape to the stream as a constant rate nutrient addition at the scale of the entire watershed—a vital scale on which to understand these processes, but for which costs and logistics of standard experiments are prohibitive. Results of this study compare patterns in dilution and uptake across spatial and temporal scales, and bound feasible explanations for hydrologic and reactive function in each reach of the network.
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Baessler, Cornelia. "Plant species diversity and genetic variation : temporal changes and spatial determinants in agricultural landscapes /". Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17734.

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Danner, Nadja [Verfasser], Ingolf [Gutachter] Steffan-Dewenter i Ricarda [Gutachter] Scheiner. "Honey bee foraging in agricultural landscapes / Nadja Danner ; Gutachter: Ingolf Steffan-Dewenter, Ricarda Scheiner". Würzburg : Universität Würzburg, 2016. http://d-nb.info/1149510269/34.

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Power, James. "Land use and vegetation change in agricultural landscapes : case studies from north-west Ireland". Thesis, University of Ulster, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267681.

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Richards, Julie Whipkey. "THE CONSERVATION VALUE OF A HEDGEROW FOR BIRDS IN AN AGRICULTURAL LANDSCAPE IN SOUTHWEST OHIO". Miami University / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=miami1019056839.

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38

Robinson, Nathan. "Assessing productive soil - landscapes in Victoria using digital soil mapping". Thesis, Federation University Australia, 2016. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/154199.

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Spatial soil information is used to support questions on agriculture and the environment from global to local scales. Historically, soil mapping has been used to inform and guide a multitude of land users with their decisions. Demand for specific spatial soil information is increasing in response from a wider range of users operating across agricultural and environmental domains. To satisfy these demands, users must be provided with practical and relevant spatial soil information. Novel approaches are required to deal with global deficiencies in available soil information. A major limitation to this is the plethora of incongruent legacy data with poor spatial and temporal coverage. This research study initially identifies the specific needs of users for spatial soil information with a focus on the requirements of biophysical modellers. Secondly, error sources that hamper Digital Soil Mapping (DSM) are identified, described and assessed using pH in practical and relevant examples. A final aim is to spatially predict soil properties (e.g. clay mineralogy) that underpin soil chemical behaviour. This is achieved by harmonising legacy data in combination with new spectroscopy techniques and a spatial inference approach. The spatial soil information needs of biophysical modellers in Victoria, Australia were found to be consistent with global needs for information including soil water characteristics, organic carbon and effective rooting depth. To accommodate stochastic and epistemic uncertainties in spatial soil information, uncertainty frameworks proved effective to deal with, and understand the limitations of legacy data in spatial inference models. Robust and reliable spectroscopic models for properties that are linked to functions and services delivered by soil were achieved and used in 3D spatial models. These findings will enable a tactical response through the delivery of pertinent spatial soil information that is contemporary, quality assured and sought by users. Learnings presented should enable producers of spatial soil information to be more comprehensive in their delivery of products that are easy to use, accessible and understood by a growing user community.
Doctor of Philosphy
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39

Chick, Hiu-lai, i 戚曉麗. "Understanding the transformation of a traditional agricultural landscape in Hong Kong: a case study of LongValley". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B47583940.

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  Cultural landscapes, as the products of long-term interaction between human and nature, have been increasingly recognized by different international bodies for their importance in heritage conservation. However, cultural landscapes usually do not enjoy specific protection and are subject to most dynamic landscape changes in modern society that impair the significance. The traditional agricultural areas in the New Territories, display unique features of organically evolved cultural landscape in Hong Kong, have disappeared in drastic rate in recent decades. Long Valley, as one of the remarkable local example of traditional agricultural landscape, was studied to illustrate the spatial and landownership transformation connected with socio-economical transition over the last century. Aerial photos comparison and Geographic Information System (GIS) were employed, and stakeholders’ interviews were conducted to aid landscape analysis.      The significance of Long Valley is embodied in the setting, natural features, resources of land and cultural context associated with the indigenous settlement and farming tradition in Hong Kong. The long history of agriculture by indigenous clans and more recently by tenant farmers defines the major landscape features of Long Valley. The aerial photographs comparison revealed that road widening, river training works, urbanization, industrialization and infrastructure development during 1960s – 1990s caused drastic environmental change and direct loss of farmland area in and surrounding Long Valley.      Combining current cadastral map with historic land plot records shows that the past lots boundaries are still influencing on today’s fieldscape of Long Valley. On the other hand, the landownership pattern of Long Valley is fragmented and complicated, and has changed continuously over the century. Indigenous clans have dominant ownership control of Long Valley but their influence is diminishing. Certain portion of lands has been transferred to developers’ and outsiders’ hands. The complicated and fragmented landownership, however, protects the site from being developed yet.      Although conservation efforts have been paid by local NGOs and the Government, Long Valley is still under threats of illegal dumping and unauthorized land-use change initiated by some indigenous landowners as well as development pressure. Traditional agricultural landscapes represent part of local natural and cultural heritage and are key component of local indigenous identity which should receive proper attention and protection. Therefore, adequate conservation and agricultural policy, effective legislation enforcement and planning control, development of adaptive conservation strategies and engagement of local stakeholders are in urge to safeguard and sustain local traditional agricultural landscapes, as well as other significant rural landscapes in Hong Kong.
published_or_final_version
Conservation
Master
Master of Science in Conservation
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40

Schweiger, Oliver. "Hierarchical top-down control of biodiversity in agricultural landscapes across organisational levels and spatial scales". [S.l.] : [s.n.], 2005. http://archiv.ub.uni-marburg.de/diss/z2005/0125/.

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41

Wehn, Sølvi. "Vegetation dynamics in seminatural cultural landscapes. - Consequences of changed agricultural practices in Eastern Jotunheimen - Norway". Doctoral thesis, Norwegian University of Science and Technology, Department of Biology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-2261.

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42

Orchard, D. G. "The population structure and demography of Triturus cristatus in agricultural landscapes of North-West England". Thesis, University of Salford, 2017. http://usir.salford.ac.uk/43733/.

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Triturus cristatus is one of Europe’s most rapidly declining amphibians and has been the subject of conservation concern in the UK since 1975. Despite its widespread decline and continued threats from development, T. cristatus remains widely distributed in the UK countryside. Traditional farming practices, such as the digging of ponds for livestock, created suitable habitats for T. cristatus and consequently the species was much more common in the past. Over the last 70 years the nature of farming has fundamentally changed and the modern landscape provides a comparatively degraded habitat for wildlife. The value of farmland for T. cristatus in the UK is often overlooked by conservation efforts for the species, even though it is a valuable habitat and essential for providing connectivity between adjacent populations. Much effort is focussed on the small number of Special Areas of Conservation (SACs) or Sites of Special Scientific Interest (SSSIs) but these cover a very small part of the UK landmass. T. cristatus has been protected by law in the UK since 1981, and as a result an estimated minimum of £45 million is spent each year to avoid killing or injuring individual newts where populations are affected by development. In contrast land in agricultural production covers 71% of the UK but funding for proactive conservation of the species across this habitat is minimal and very difficult to obtain. This thesis has investigated the ecology of T. cristatus on farmland in North West England. Data were collected from a total of 32 ponds on 11 sites. Population size estimates are presented for eight farm ponds and are compared with those from three non-farmed ponds. Population size varied markedly between ponds and sites, and some farm ponds supported very small numbers of newts. Population estimates fluctuated markedly between years, highlighting the importance of long term studies. Isolated ponds supported relatively large numbers of individuals, and indeed the highest population estimate was recorded in an isolated pond. This demonstrates that isolation in itself is not a limiting factor for population size. In total, 4693 individuals captured during this study were weighed and measured, and the data were used to compare body condition index (BCI) between populations. There was no clear difference between BCI at farmed and non-farmed sites, suggesting that BCI of T. cristatus on farmland was not adversely affected by modern farming practices. There was an inverse relationship between age and body condition. The age structure of 13 populations was estimated based on skeletochronology of 548 adults. Individuals in the farmed landscape survived to a maximum estimated age of 14 years, only one year less than the maximum age recorded during this study. Twenty individuals were estimated at 12 years or older. Fourteen of these were from farmed and six were from non-farmed populations. This indicates that both the aquatic and terrestrial habitat of the farmed landscape is sufficient to allow newts to fulfil their natural lifespan. The estimated age of sexual maturity for the majority of individuals was 2-3 years. The median estimated age across all populations was 6.5 years for males and seven years for females. It appears that individuals do not breed as soon as they reach sexual maturity and thus remain in the terrestrial habitat for a much longer period of their lives than previously thought. Males always returned to the pond earlier than females of the same age. In both sexes, individuals aged 8 years and over were on average captured approximately three weeks prior to younger individuals. Whether population isolation has had any measurable effect on T. cristatus was investigated using a genetic study of 23 populations on 13 sites. There was no evidence of a loss of genetic diversity through isolation. This study supported the conclusion of other research that dispersal distances for T. cristatus can be much greater than reported by capture-mark-recapture (C-M-R) studies. At one of the farmed sites (Moss Shaw Farm), populations just over 1 km apart were assigned similar genetic characteristics, indicating genetic mixing of those populations. This shows that the modern agricultural landscape is still capable of facilitating the dispersal of individuals. The results of this research demonstrate that the agricultural landscape in the UK can continue to provide a suitable habitat for T. cristatus. Efforts to engage with farmers and landowners to enlist their support for the conservation of this species will therefore be worthwhile.
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43

Bardsley, Louise. "Use and selection of terrestrial resources by adult common toads (Bufo bufo) in agricultural landscapes". Thesis, De Montfort University, 1998. http://hdl.handle.net/2086/5851.

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Santos, Jose Manuel. "Valuation and cost-benefit analysis of multi-attribute environmental changes : upland agriculture landscapes in England and Portugal". Thesis, University of Newcastle Upon Tyne, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361563.

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Henris, John Robert. "Apples Abound: Farmers, Orchards, and the Cultural Landscapes of Agrarian Reform, 1820-1860". Akron, OH : University of Akron, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=akron1239648392.

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Dissertation (Ph. D.)--University of Akron, Dept. of History, 2009.
"May, 2009." Title from electronic dissertation title page (viewed 11/27/2009) Advisor, Kevin Kern; Committee members, Lesley J. Gordon, Kim M. Gruenwald, Elizabeth Mancke, Randy Mitchell, Gregory Wilson; Department Chair, Michael M. Sheng; Dean of the College, Chand Midha; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.
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46

Elsayed, Ali Hamada [Verfasser], i Björn [Akademischer Betreuer] Reineking. "Plant communities in field margins of agricultural landscapes: species distributions, functional traits, and contributions to landscape function / Hamada Elsayed Ali. Betreuer: Björn Reineking". Bayreuth : Universität Bayreuth, 2015. http://d-nb.info/1077818831/34.

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Bert, Daniel G. "A multiscale analysis of nested species subsets of forest birds in agricultural landscapes near Ottawa, Canada". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ57784.pdf.

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Latham, Dorian Miles. "The terrestrial habitat selection and utilisation by the common toad (Bufo bufo L.) in agricultural landscapes". Thesis, De Montfort University, 1997. http://hdl.handle.net/2086/5853.

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49

Malinga, Rebecka. "Ecosystem services in agricultural landscapes : A study on farming and farmers in South Africa and Sweden". Doctoral thesis, Stockholms universitet, Stockholm Resilience Centre, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-133485.

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Humanity is facing challenges of sustainably producing enough food for a growing population without further eroding the world’s ecosystems. Transformation of natural habitats into agriculture has resulted in opportunities for civilization, but has also led to land degradation and loss of biodiversity, threatening the generation of ecosystem services. A better understanding of interlinkages and trade-offs among ecosystem services, and the spatial scales at which services are generated, used and interact, is needed in order to successfully inform land use policies. This includes the need to develop transdisciplinary tools that can disentangle the relationships between the supply of and demand for ecosystem services. This thesis investigates agricultural landscapes as complex social-ecological systems, and uses a multi-method approach to assess ecosystem service generation from different types of agricultural landscapes and to examine the social-ecological nature of these services. More specifically, the thesis discusses the importance of appropriate spatial scales, explores landscape change, integrates stakeholder knowledge and develops tools to investigate supply and demand of multiple ecosystem services.  Paper I reviews the literature on ecosystem service mapping, revealing that services were mostly mapped at intermediate spatial scales (municipality and province), and rarely at local scales (farm/village). Although most of the reviewed studies used a resolution of 1 hectare or less, more case-specific local scale mapping is required to unravel the fine-scale dynamics of ecosystem service generation that are needed to inform landscape planning. To explore future uncertainties and identify relevant ecosystem services in a study area, paper II builds alternative scenarios using participatory scenario planning in the Upper Thukela region, South Africa. The paper compares methods to select services for an ecosystem service assessment showing that scenario planning added limited value for identifying ecosystem services, although it improved knowledge of the study area and availed useful discussions with stakeholders. Papers III and IV combines social and biophysical data to study the supply and demand of ecosystem services at farm- and landscape level, through participatory mapping and expert assessments in the Upper Thukela region, South Africa (paper III), and through in-depth interviews and biophysical surveys in Uppsala County, Sweden (paper IV), including small-scale and large-scale farmers. Both papers find apparent differences between the farmer groups in terms of the supply and the demand of services, and also the capacity of the farmers to influence the generation of services (paper III). Paper IV further establishes the importance of using multiple indicators combining social and biophysical data to quantify and investigate the complex social-ecological nature of ecosystem services. A cross-case comparison of ecosystem service bundles, using data from papers III and IV, finds similarities in bundles generated in the large-scale systems, while the small-scale agriculture bundles varied. This thesis provides new insights into the social-ecological generation of ecosystem services at fine scales such as farm and landscape levels, and shows the importance of including the knowledge of various stakeholders, combining different methods and tools to increase the understanding of supply and demand of ecosystem services.

At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 3: Manuscript.

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Bert, Daniel G. (Daniel George) Carleton University Dissertation Biology. "A multiscale analysis of nested species subsets of forest birds in agricultural landscapes near Ottawa, Canada". Ottawa, 2001.

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