The future climate adapted gardens : the green rooms of Elisefarm: a garden design study focused on plants

I det här examensarbetet undersöks möjlig gestaltning av växtval för att motverka och bli anpassade till klimatförändringarna i Skåne år 2055. De förhöjda mängderna växthusgaser i atmosfären påverkar temperaturen i på jorden. På norra halvklotet kommer klimatzonerna flyttas mot nordligare breddgrader. Klimatet i Skåne kommer att förändras på grund av klimatförändringarna och därmed även växtligheten. Sommarhalvåret kommer att bli varmare, nederbörden kommer minska och vegetationsperioden bli längre. Därmed kommer detta att påverka vilka växter som kan användas i trädgårdssammanhang för att klara de nya förändrade väderförhållanden. Ett nytt bostadsområde ska uppföras på Elisefarms mark och två tomter kommer i det här examensarbetet att gestaltas efter dess ståndort ur ett nytt klimatperspektiv. Uppdraget går ut på att göra två tilltalande förslag med växterna i fokus. Arbetets syfte är att informera trädgårdsägare växternas verkan på klimatet och val av växter. Frågeställningarna undersöks genom litteratur för att kartlägga framtidens klimat i Skåne samt genom att studera bäst lämpligt växtmaterial som kan mildra eller passa in på den framtida klimatsituationen samt gestalta tomterna ur bästa klimatperspektiv. Två ståndpunkter som tagits i beaktning. Hur kan vi/ eller kan vi genom smart planering av små trädgårdar bidra till att minska vår påverkan på klimatet och bromsa den negativa utvecklingen? Vilka växtval ska göras med växtlighet givet de förändringar som sker i vår klimatzon? Växtlistor med främst perenner tas fram med grund av litteraturen och genereras till gestaltningen. Arbetet frambringar illustrationsplaner, sektioner, planteringsplaner som förmedlar för blivande tomtägare och läsare.This thesis examines possible design of plant selection to counteract and to adapt to the climate changes in Skåne in 2055. The increased amounts of greenhouse gasses in the atmosphere affect the temperature on earth. In the Northern Hemisphere, the climate zones will be moved towards more northerly latitudes. The climate in Skåne will change due to the climate changes and thus the vegetation as well. The summer semester will be warmer, precipitation will decrease and the vegetation period will be longer. Thus, this will affect which plants can be used in a garden context to cope with the new changed weather conditions. A new residential area is to be built on Elisefarm’s land, and two plots of land will be studied in this thesis according to their location from a new climate perspective. The task is to make two additional proposals with the plants in focus. The aim of the work is to inform garden owners about the effects of plants on the climate and the choice of plants. The questions are investigated through literature in order to map the future climate in Scania and by studying the most suitable plant material that can mitigate or fit into the future climate situation and shape the plots from the best climate perspective. Two positions taken into consideration are How can/or can we, through smart planning of small gardens, contribute to reducing our impact on the climate and slow down negative developments? What plant choices should be made with vegetation given the changes that are occurring in our climate zone? Plant lists with mainly perennials are produced on the basis of the literature and generated for the design. The work produces illustration plans, sections, planting plans that convey to prospective plot owners and readers

Cancellous bone and theropod dinosaur locomotion. Part II—a new approach to inferring posture and locomotor biomechanics in extinct tetrapod vertebrates

This paper is the second of a three-part series that investigates the architecture of cancellous bone in the main hindlimb bones of theropod dinosaurs, and uses cancellous bone architectural patterns to infer locomotor biomechanics in extinct non-avian species. Cancellous bone is widely known to be highly sensitive to its mechanical environment, and therefore has the potential to provide insight into locomotor biomechanics in extinct tetrapod vertebrates such as dinosaurs. Here in Part II, a new biomechanical modelling approach is outlined, one which mechanistically links cancellous bone architectural patterns with three-dimensional musculoskeletal and finite element modelling of the hindlimb. In particular, the architecture of cancellous bone is used to derive a single ‘characteristic posture’ for a given species—one in which bone continuum-level principal stresses best align with cancellous bone fabric—and thereby clarify hindlimb locomotor biomechanics. The quasi-static approach was validated for an extant theropod, the chicken, and is shown to provide a good estimate of limb posture at around mid-stance. It also provides reasonable predictions of bone loading mechanics, especially for the proximal hindlimb, and also provides a broadly accurate assessment of muscle recruitment insofar as limb stabilization is concerned. In addition to being useful for better understanding locomotor biomechanics in extant species, the approach hence provides a new avenue by which to analyse, test and refine palaeobiomechanical hypotheses, not just for extinct theropods, but potentially many other extinct tetrapod groups as well

Motor control of locomotor hindlimb posture in the American alligator (Alligator mississippiensis)

Crocodilians are unusual among quadrupedal tetrapods in their frequent use of a wide variety of hindlimb postures, ranging from sprawling to a more erect high walk. In this study, we use synchronized kinematic videos and electromyographic recordings to test how the activity patterns of hindlimb muscles in American alligators (Alligator mississippiensis Daudin) differ between sprawling and more upright postures. Previous force platform analyses suggested that upright posture in alligators would require greater activation by hindlimb extensors to counter increases in the flexor moments exerted about joints by the ground reaction force during upright stance. Consistent with these predictions, ankle extensors (gastrocnemius) and knee extensors (femorotibialis internus and iliotibialis 2) exhibit increases in signal intensity during the use of more upright stance. Bone loading data also predicted that activation patterns for hip adductors spanning the length of the femur would not differ between sprawling and more upright posture. Correspondingly, motor patterns of the adductor femoris were not altered as posture became more upright. However, the adductor puboischiofemoralis externus 3, which inserts far proximally on the femur, displays significant increases in burst intensity that could contribute to the greater femoral adduction that is integral to upright posture. In contrast to patterns in alligators, in mammals EMG burst intensity typically decreases during the use of upright posture. This difference in the motor control of limb posture between these taxa may be related to differences in the relative sizes of their feet. Alligator feet are large relative to the hindlimb and, as a result, the ground reaction force shifts farther from the limb joints during upright steps than in mammals, increasing flexor moments at joints and requiring alligator extensor muscles to exert greater forces to keep the limb in equilibrium. However, several alligator hindlimb muscles show no differences in motor pattern between sprawling and upright posture. The wide range of motor pattern modulations between different postures in alligators suggests considerable independence of neural control among the muscles of the alligator hindlimb

Cancellous bone and theropod dinosaur locomotion. Part I—an examination of cancellous bone architecture in the hindlimb bones of theropods

This paper is the first of a three-part series that investigates the architecture of cancellous (‘spongy’) bone in the main hindlimb bones of theropod dinosaurs, and uses cancellous bone architectural patterns to infer locomotor biomechanics in extinct non-avian species. Cancellous bone is widely known to be highly sensitive to its mechanical environment, and has previously been used to infer locomotor biomechanics in extinct tetrapod vertebrates, especially primates. Despite great promise, cancellous bone architecture has remained little utilized for investigating locomotion in many other extinct vertebrate groups, such as dinosaurs. Documentation and quantification of architectural patterns across a whole bone, and across multiple bones, can provide much information on cancellous bone architectural patterns and variation across species. Additionally, this also lends itself to analysis of the musculoskeletal biomechanical factors involved in a direct, mechanistic fashion. On this premise, computed tomographic and image analysis techniques were used to describe and analyse the three-dimensional architecture of cancellous bone in the main hindlimb bones of theropod dinosaurs for the first time. A comprehensive survey across many extant and extinct species is produced, identifying several patterns of similarity and contrast between groups. For instance, more stemward non-avian theropods (e.g. ceratosaurs and tyrannosaurids) exhibit cancellous bone architectures more comparable to that present in humans, whereas species more closely related to birds (e.g. paravians) exhibit architectural patterns bearing greater similarity to those of extant birds. Many of the observed patterns may be linked to particular aspects of locomotor biomechanics, such as the degree of hip or knee flexion during stance and gait. A further important observation is the abundance of markedly oblique trabeculae in the diaphyses of the femur and tibia of birds, which in large species produces spiralling patterns along the endosteal surface. Not only do these observations provide new insight into theropod anatomy and behaviour, they also provide the foundation for mechanistic testing of locomotor hypotheses via musculoskeletal biomechanical modelling

In vivo femoral strains in swimming turtles: Influence of locomotor medium on limb bone loading

The transition from aquatic to terrestrial habitats was an event in vertebrate evolution that preceded a sudden radiation of species. Subsequently some vertebrate lineages have returned to their ancestral aquatic habitats. It is known that vertebrate bone structure can vary depending on habitat. The evolutionary explanation for this is attributable to the fact that loads on the skeleton varies depending on the environment organisms inhabit. Terrestrial vertebrates would be expected to experience greater loads on their bones versus aquatic vertebrates due to body support demands, but there are no experimental data to test this hypothesis or quantify the difference. We tested how loads differed on the appendicular skeleton between use in terrestrial and aquatic habitats by recoding in vivo femoral strains during swimming and walking in turtles. We predicted that since swimming exerts less force on the limbs, peak load magnitudes would be lower during swimming versus walking, but that load peaks would be nearly equal during the thrust and recovery phases of the swimming limb cycle. Our data support our first prediction, with average peak strain magnitudes of swimming being half those of walking. Loading regimes were similar between both swimming and walking with compressive axial strains experienced dorsally on the femur. However, our second prediction was not supported, because peak strains were much higher during the thrust phase. Our results indicate that even when environmental forces are lessened, limb muscles play a large role in the production of bone loads

Mechanics of limb bone loading during terrestrial locomotion in river cooter turtles (Pseudemys concinna)

Studies of limb bone loading during terrestrial locomotion have focused primarily on birds and mammals. However, data from a broader functional and phylogenetic range of species are critical for understanding the evolution of limb bone function and design. Turtles are an interesting lineage in this context. Although their slow walking speeds and robust limb bones might lead to low locomotor forces and limb bone stresses similar to other non-avian reptiles, their highly sprawled posture could produce high bending loads, leading to high limb bone stresses similar to those of avian and mammalian species, as well as high torsion. To test between these possibilities, we evaluated stresses experienced by the femur of river cooter turtles (Pseudemys concinna) during terrestrial walking by synchronizing measurements of three-dimensional joint kinematics and ground reaction forces (GRFs) during isolated hindlimb footfalls. Further, we evaluated femoral safety factors for this species by comparing our locomotor stress calculations with the results of mechanical property tests. The net GRF magnitude at peak tensile bone stress averaged 0.35 BW (body weight) and was directed nearly vertically for the middle 40–65% of the contact interval, essentially orthogonal to the femur. Peak bending stresses experienced by the femur were low (tensile: 24.9±9.0 MPa; compressive: –31.1±9.1 MPa) and comparable to those in other reptiles, yet peak shear stresses were higher than those in other reptiles, averaging 13.7±4.2 MPa. Such high torsion is present despite cooters lacking a large tail, a feature that has been hypothesized to contribute to torsion in other reptiles in which the tail is dragged along the ground. Comparison of femoral stresses to measurements of limb bone mechanical properties in cooters indicates safety factors to yield of 13.9 in bending and 6.3 in torsion, considerably higher than values typical for birds and mammals, and closer to the elevated values calculated for other reptile species. Thus, not only do turtle limb bones seem considerably `over-designed\u27 for resisting the loads that they encounter, but comparisons of bone loading across tetrapod lineages are consistent with the hypothesis that low limb bone loads, elevated torsion and high safety factors may be primitive features of limb bone design

Mechanics of limb bone loading during terrestrial locomotion in the green iguana (Iguana iguana) and American alligator (Alligator mississippiensis)

In vivo measurements of strain in the femur and tibia of Iguana iguana (Linnaeus) and Alligator mississippiensis (Daudin) have indicated three ways in which limb bone loading in these species differs from patterns observed in most birds and mammals: (i) the limb bones of I. iguana and A. mississippiensis experience substantial torsion, (ii) the limb bones of I. iguana and A. mississippiensis have higher safety factors than those of birds or mammals, and (iii) load magnitudes in the limb bones of A. mississippiensis do not decrease uniformly with the use of a more upright posture. To verify these patterns, and to evaluate the ground and muscle forces that produce them, we collected three-dimensional kinematic and ground reaction force data from subadult I. iguana and A. mississippiensis using a force platform and high-speed video. The results of these force/kinematic studies generally confirm the loading regimes inferred from in vivo strain measurements. The ground reaction force applies a torsional moment to the femur and tibia in both species; for the femur, this moment augments the moment applied by the caudofemoralis muscle, suggesting large torsional stresses. In most cases, safety factors in bending calculated from force/video data are lower than those determined from strain data, but are as high or higher than the safety factors of bird and mammal limb bones in bending. Finally, correlations between limb posture and calculated stress magnitudes in the femur of I. iguana confirm patterns observed during direct bone strain recordings from A. mississippiensis: in more upright steps, tensile stresses on the anterior cortex decrease, but peak compressive stresses on the dorsal cortex increase. Equilibrium analyses indicate that bone stress increases as posture becomes more upright in saurians because the ankle and knee extensor muscles exert greater forces during upright locomotion. If this pattern of increased bone stress with the use of a more upright posture is typical of taxa using non-parasagittal kinematics, then similar increases in load magnitudes were probably experienced by lineages that underwent evolutionary shifts to a non-sprawling posture. High limb bone safety factors and small body size in these lineages could have helped to accommodate such increases in limb bone stress

In vivo locomotor strain in the hind limb bones of Alligator mississipiensis and Iguana iguana: implications for the evolution of limb bone safety factor and non-sprawling limb posture.

Limb postures of terrestrial tetrapods span a continuum from sprawling to fully upright; however, most experimental investigations of locomotor mechanics have focused on mammals and ground-dwelling birds that employ parasagittal limb kinematics, leaving much of the diversity of tetrapod locomotor mechanics unexplored. This study reports measurements of in vivo locomotor strain from the limb bones of lizard (Iguana iguana) and crocodilian (Alligator mississippiensis) species, animals from previously unsampled phylogenetic lineages with non-parasagittal limb posture and kinematics. Principal strain orientations and shear strain magnitudes indicate that the limb bones of these species experience considerable torsion during locomotion. This contrasts with patterns commonly observed in mammals, but matches predictions from kinematic observations of axial rotation in lizard and crocodilian limbs. Comparisons of locomotor load magnitudes with the mechanical properties of limb bones in Alligator and Iguana indicate that limb bone safety factors in bending for these species range from 5.5 to 10.8, as much as twice as high as safety factors previously calculated for mammals and birds. Limb bone safety factors in shear (3.9-5.4) for Alligator and Iguana are also moderately higher than safety factors to yield in bending for birds and mammals. Finally, correlations between limb posture and strain magnitudes in Alligator show that at some recording locations limb bone strains can increase during upright locomotion, in contrast to expectations based on size-correlated changes in posture among mammals that limb bone strains should decrease with the use of an upright posture. These data suggest that, in some lineages, strain magnitudes may not have been maintained at constant levels through the evolution of a non-sprawling posture unless the postural change was accompanied by a shift to parasagittal kinematics or by an evolutionary decrease in body size

Comparison of beam theory and finite-element analysis with in vivo bone strain data from the alligator cranium

The mechanical behavior of the vertebrate skull is often modeled using free-body analysis of simple geometric structures and, more recently, finite-element (FE) analysis. In this study, we compare experimentally collected in vivo bone strain orientations and magnitudes from the cranium of the American alligator with those extrapolated from a beam model and extracted from an FE model. The strain magnitudes predicted from beam and FE skull models bear little similarity to relative and absolute strain magnitudes recorded during in vivo biting experiments. However, quantitative differences between principal strain orientations extracted from the FE skull model and recorded during the in vivo experiments were smaller, and both generally matched expectations from the beam model. The differences in strain magnitude between the data sets may be attributable to the level of resolution of the models, the material properties used in the FE model, and the loading conditions (i.e., external forces and constraints). This study indicates that FE models and modeling of skulls as simple engineering structures may give a preliminary idea of how these structures are loaded, but whenever possible, modeling results should be verified with either in vitro or preferably in vivo testing, especially if precise knowledge of strain magnitudes is desired. (c) 2005 Wiley-Liss, Inc