4,820 research outputs found

    Floristic diversity of the Divlja─Źa forest (eastern Medvednica)

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    ┼áuma Divlja─Źa nalazi se u Sesvetama, sa zapadne strane naslanja se na zagreba─Źku ─Źetvrt Dubrava, a sa njene sjeverozapadne strane prostire se Medvednica. U istra┼żivanom podru─Źju pojavljuju se razli─Źita mikrostani┼íta: bjelogorica, crnogorica, kr─Źevine, obale potoka i sastojine malog zimzelena. Vaskularna flora ovog podru─Źja istra┼żivana je od velja─Źe do studenog 2022. godine. Zabilje┼żeno je 114 vrsta raspore─Ĺenih u 54 biljne porodice. Najbrojnije biljne porodice su Rosaceae (10%), Compositae (8%), Ranunculaceae (5%), Fabaceae (4%), Scrophulariaceae (4%), Apiaceae (3%), Caryophyllaceae (3%), Juncaceae (3%) i Lamiaceae (3%). Najve─çi broj vrsta i raznolikost je na kr─Źevinama. Najdominantniji ┼żivotni oblici su dugo┼żivu─çi hemikriptofiti (41,23%), geofiti (25,44%) i fanerofiti (19,3%). Na svim mikrostani┼ítima dominiraju listopadne biljke. Dominantni oblici rasprostranjivanja su endohorija, disohorija i mirmekohorija. Fitogeografska analiza pokazuje da u istra┼żivanom podru─Źju dominiraju biljke euroazijskog flornog elementa (40,9%). Na svim mikrostani┼ítima prevladavaju biljke kojima odgovaraju temperature bre┼żuljkastog pojasa te biljke suboceanske do subkontinentalne rasprostranjenosti. Zabilje┼żeno je osam alohtonih i ─Źetiri invazivne vrste. Prema Crvenoj knjizi vaskularne flore Hrvatske 6 svojti svrstano je u neko od kategorija ugro┼żenosti.The Divlja─Źa Forest is located in Sesvete, on the west side it abuts the Zagreb district of Dubrava, and on its northwest side lies Medvednica. Different microhabitats appear in the researched area: spruce, coniferous, scrub, stream banks and stands of Vinca minor. The vascular flora of this area was investigated from February to November 2022. 114 taxa distributed in 54 plant families were recorded. The most represented plant families are Rosaceae (10%), Compositae (8%), Ranunculaceae (5%), Fabaceae (4%), Scrophulariaceae (4%), Apiaceae (3%), Caryophyllaceae (3%), Juncaceae (3%) and Lamiaceae (3%). The greatest number of species and diversity is in scrubland. The most dominant life forms are long-lived hemicryptophytes (41.23%), geophytes (25.44%) and phanerophytes (19.3%). All microhabitats are dominated by deciduous plants. The dominant forms of propagation are endochory, disochory and myrmecochory. Phytogeographical analysis shows that plants of the Eurasian floral element dominate in the researched area (40.9%). All microhabitats are dominated by plants that correspond to the temperatures of the hilly belt and plants of suboceanic to subcontinental distribution. Eight allochthonous and four invasive species were recorded. According to the Red Book of the Vascular Flora of Croatia, 6 taxa are classified in one of the endangered categories

    Holocene Vegetation, Drought, and Fire Variability in the Northern Great Basin, Oregon

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    The Northern Great Basin of Oregon is an area of diverse ecologies organized along elevational gradients and variable water sources. At the lowest elevations are the remnants of Pleistocene pluvial lakes, now deflated alkaline playas. Sagebrush (Artemisia tridentata) steppe dominates the region, and anywhere there is water at or very near the surface, marshes are present. At higher elevations open dry-forest systems begin appearing, composed primarily of Pinus ponderosa, but also including Pinus contorta and Juniperus occidentalis. Populus tremuloides is also found in greater abundance at these mid-elevation areas. High-elevation sites often host mixed conifer forests, subalpine forests, and some alpine conditions, with white-bark pine (Pinus albicaulis) found at some of the highest peaks. During the Pleistocene atmospheric conditions were cooler than present day, and evapotranspiration was much lower, resulting in the formation of large lakes. There were also glaciers present in some places, as well as locations too cold and dry to form glaciers.Climatic conditions began changing rapidly beginning ca. 12,000 years ago (Mehringer 1987; Wigand 1987). Maximum insolation continued warming the planet and peaked by 11,000 years ago most of the continental ice sheets were rapidly retreating while montane glaciers in the NGB had already retreated (Osborn and Beavis, 2001). By 9000 years ago maximum air temperatures and increased aridity resulted in the Northern Great Basin pluvial lakes desiccating and many vegetation communities shifting upward in elevation. Such climate changes would also cause fire event frequency to also change during this time, resulting in conditions and disturbance timings very different than the current day. Towards the end of the early Holocene the catastrophic eruption of Mount Mazama in ca. 7640 cal yr BP (Egan, 2015) would again alter vegetation communities and fire events to varying degrees depending on locations relative to the main eruption blast zone. Despite periodic droughts climatic conditions in the NGB have generally cooled through the late Holocene, with vegetation communities again responding. (Benson et al., 1997; Minckley et al., 2007; Marsicek et al., 2018). With an emphasis on the Holocene, questions behind this dissertation were driven by asking 1) by how much did vegetation communities change in the Northern Great Basin responding to changes in climate and fire, 2) which taxa changed the least, which the most, and was it climate or fire that drove those changes, 3) by how much is it possible to observe regional or local drought severity, and 4) by how much and when did climatic timing in the Northern Great Basin differ from Central and Southern Great Basin regions, if at all? To address these broad questions three locations were identified as good study sites. These three locations are within 40 km of each other but at different elevations. Differing elevations were sought for the purpose of attempting to determine what the rate of ecological change was for each location. There are few records showing continuous ecological and fire records at different elevations in the NGB from the early Holocene through to today, but of the records that do remain a rich history of variable timing for fire histories and ecological community structures are sharply delineated and preserved (Gruell, 1995; Minckley et al., 2007). Environmental conditions were reconstructed using traditional and novel methods for three sites identified as ideal for contributing ecological perspectives that would overlap in time. To reconstruct ecological settings, pollen was the primary data source for all three sites. Pollen assemblages provide a view of the climatic conditions at a given point in time, but in some cases may not reflect the full context of conditions as other variables such as tephra or charcoal may alter interpretations. Iin the case of coprolite pollen, a false sense of what vegetation is present on the landscape and in what abundances can occur. When available, carbon and nitrogen concentrations show how climate affected lake productivity, and charcoal provides insights on the fire-adapted landscape and how vegetation responded to changing arid conditions and fire events over time. Chapter 2 examines the late Pleistocene through early Holocene environmental conditions at a low-elevation site by contrasting the regional pollen signal preserved in the sediments of Paisley Caves to the more focused and hyper-local pollen found in chronologically contemporaneous coprolites produced by medium to large-sized mammals as they moved across their ancient landscapes. The results show several consistent differences in pollen assemblage composition in the coprolites compared to the sediments, consistent with the coprolite producers favoring certain environments prior to depositing coprolites in a cave. Chapter 3 examines the history of a rare mid-elevation freshwater lake in the NGB. Dog Lake is a landslide-formed lake whose lake level fluctuates annually, but remained very low during the early Holocene, followed by a period of low lake productivity and lower vegetation cover between 8700 and 8200 cal yr BP, then deepened to a point it resembled depths seen today. Using pollen, C and N concentrations, plant macrofossils, and charcoal, we found when lake productivity was low resulting from increased aridity in the early Holocene, there was also fewer fire episodes than expected from climate, likely due to low fuel availability and probably fewer ignition events. Fire frequencies increased with cooling temperatures and increased effective moisture during the middle Holocene. Chapter 4 describes the fire and hydrological history of White Pine Marsh (WPMA), a high-elevation site located in a small cirque valley at the northern terminus of the Warner Mountains. The site is in a mesic, mixed conifer forest with the perennial marsh having formed after the Mazama eruption and subsequent deposition of tephra in the basin. Sediments also show the fire history was also altered by the tephra. Charcoal showed fires were more frequent and increased in intensity during the early Holocene, abruptly changing to lower intensity and longer fire intervals post-Mazama. Pollen showed mixed conifer conditions since 9500 cal yr BP with Pinus ponderosa always dominant with variable presence of Abies. This dissertation includes published and unpublished co-authored material. At the time of writing Chapter 2 is in press at Quaternary Review. Co-authors include Daniel Gavin, Erin Herring, and Dennis Jenkins. Herring processed the coprolites and provided analysis descriptions. Jenkins provided site expertise to this paper. Gavin and Saban conceptualized the study and devised the methodology of analysis. Both Gavin and Saban analyzed the sedimentary lithological components. Saban wrote the original manuscript with GavinÔÇÖs help in the analysis and visualization of the data. Gavin also reviewed, edited, and contributed to the final manuscript. In chapter 3 Saban and Gavin conceptualized the study and analyzed sediments. Saban analyzed the pollen and charcoal. Analysis and data visualizations were significantly aided by Gavin while Saban wrote the original manuscript. Gavin further reviewed, edited, and contributed to the final manuscript. In chapter 4 Saban and Gavin conceptualized the study and devised the research methodology as well as analyzed the sediments, while Saban processed and analyzed pollen and charcoal. Saban wrote the original paper, and Gavin reviewed, edited, and contributed to the final manuscript

    Floristic diversity of the Divlja─Źa forest (eastern Medvednica)

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    ┼áuma Divlja─Źa nalazi se u Sesvetama, sa zapadne strane naslanja se na zagreba─Źku ─Źetvrt Dubrava, a sa njene sjeverozapadne strane prostire se Medvednica. U istra┼żivanom podru─Źju pojavljuju se razli─Źita mikrostani┼íta: bjelogorica, crnogorica, kr─Źevine, obale potoka i sastojine malog zimzelena. Vaskularna flora ovog podru─Źja istra┼żivana je od velja─Źe do studenog 2022. godine. Zabilje┼żeno je 114 vrsta raspore─Ĺenih u 54 biljne porodice. Najbrojnije biljne porodice su Rosaceae (10%), Compositae (8%), Ranunculaceae (5%), Fabaceae (4%), Scrophulariaceae (4%), Apiaceae (3%), Caryophyllaceae (3%), Juncaceae (3%) i Lamiaceae (3%). Najve─çi broj vrsta i raznolikost je na kr─Źevinama. Najdominantniji ┼żivotni oblici su dugo┼żivu─çi hemikriptofiti (41,23%), geofiti (25,44%) i fanerofiti (19,3%). Na svim mikrostani┼ítima dominiraju listopadne biljke. Dominantni oblici rasprostranjivanja su endohorija, disohorija i mirmekohorija. Fitogeografska analiza pokazuje da u istra┼żivanom podru─Źju dominiraju biljke euroazijskog flornog elementa (40,9%). Na svim mikrostani┼ítima prevladavaju biljke kojima odgovaraju temperature bre┼żuljkastog pojasa te biljke suboceanske do subkontinentalne rasprostranjenosti. Zabilje┼żeno je osam alohtonih i ─Źetiri invazivne vrste. Prema Crvenoj knjizi vaskularne flore Hrvatske 6 svojti svrstano je u neko od kategorija ugro┼żenosti.The Divlja─Źa Forest is located in Sesvete, on the west side it abuts the Zagreb district of Dubrava, and on its northwest side lies Medvednica. Different microhabitats appear in the researched area: spruce, coniferous, scrub, stream banks and stands of Vinca minor. The vascular flora of this area was investigated from February to November 2022. 114 taxa distributed in 54 plant families were recorded. The most represented plant families are Rosaceae (10%), Compositae (8%), Ranunculaceae (5%), Fabaceae (4%), Scrophulariaceae (4%), Apiaceae (3%), Caryophyllaceae (3%), Juncaceae (3%) and Lamiaceae (3%). The greatest number of species and diversity is in scrubland. The most dominant life forms are long-lived hemicryptophytes (41.23%), geophytes (25.44%) and phanerophytes (19.3%). All microhabitats are dominated by deciduous plants. The dominant forms of propagation are endochory, disochory and myrmecochory. Phytogeographical analysis shows that plants of the Eurasian floral element dominate in the researched area (40.9%). All microhabitats are dominated by plants that correspond to the temperatures of the hilly belt and plants of suboceanic to subcontinental distribution. Eight allochthonous and four invasive species were recorded. According to the Red Book of the Vascular Flora of Croatia, 6 taxa are classified in one of the endangered categories

    Seed dispersal between aquatic and agricultural habitats by greylag geese

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    Waterbirds disperse plant seeds within and between aquatic and terrestrial ecosystems in their faeces. However, seed dispersal distances, connectivity among habitat types, and implications for dispersal of weeds remain unquantified in agricultural landscapes. Therefore, we GPS-tagged 31 greylag geese Anser anser and collected 300 faecal samples from feeding flocks in seven agricultural habitats (four cereals, hayfields, pasture, and strawberries) across two landscapes in southern Sweden. We identified intact seeds, determined key plant traits, and tested three hypotheses: (1) geese ingest, transport, and egest seeds from a wide range of terrestrial and aquatic plants, including weeds and alien species; (2) the community and trait composition of plant seeds in faeces vary between habitat types; and (3) seed dispersal by geese is a directional dispersal mechanism that connects some habitat types more than others. We recovered 131 seeds from 41 plant species (19 families), including nine agricultural weeds and one alien species. Many seeds were from aquatic plants (45%), dispersed into terrestrial habitats. A connectivity network formed between habitat types (as nodes) and direct flights (as links) revealed that all agricultural habitats were directly connected with each other, although 66% of flights were between aquatic and agricultural habitats. Geese spent most time at lakes (34%), pastures (14%), barley (10%) and wheat (8%) fields, which were also the most interconnected habitats, with high seed species richness and seed abundance in faecal samples. Combining waterfowl movement data with faecal analysis provided support for all three hypotheses. Geese may contribute to previously overlooked agricultural conflicts through weed dispersal. Proximity to aquatic habitats suitable for roosting may increases the use of agricultural habitats, and potentially the seed dispersal into them

    Floristic diversity of the Divlja─Źa forest (eastern Medvednica)

    No full text
    ┼áuma Divlja─Źa nalazi se u Sesvetama, sa zapadne strane naslanja se na zagreba─Źku ─Źetvrt Dubrava, a sa njene sjeverozapadne strane prostire se Medvednica. U istra┼żivanom podru─Źju pojavljuju se razli─Źita mikrostani┼íta: bjelogorica, crnogorica, kr─Źevine, obale potoka i sastojine malog zimzelena. Vaskularna flora ovog podru─Źja istra┼żivana je od velja─Źe do studenog 2022. godine. Zabilje┼żeno je 114 vrsta raspore─Ĺenih u 54 biljne porodice. Najbrojnije biljne porodice su Rosaceae (10%), Compositae (8%), Ranunculaceae (5%), Fabaceae (4%), Scrophulariaceae (4%), Apiaceae (3%), Caryophyllaceae (3%), Juncaceae (3%) i Lamiaceae (3%). Najve─çi broj vrsta i raznolikost je na kr─Źevinama. Najdominantniji ┼żivotni oblici su dugo┼żivu─çi hemikriptofiti (41,23%), geofiti (25,44%) i fanerofiti (19,3%). Na svim mikrostani┼ítima dominiraju listopadne biljke. Dominantni oblici rasprostranjivanja su endohorija, disohorija i mirmekohorija. Fitogeografska analiza pokazuje da u istra┼żivanom podru─Źju dominiraju biljke euroazijskog flornog elementa (40,9%). Na svim mikrostani┼ítima prevladavaju biljke kojima odgovaraju temperature bre┼żuljkastog pojasa te biljke suboceanske do subkontinentalne rasprostranjenosti. Zabilje┼żeno je osam alohtonih i ─Źetiri invazivne vrste. Prema Crvenoj knjizi vaskularne flore Hrvatske 6 svojti svrstano je u neko od kategorija ugro┼żenosti.The Divlja─Źa Forest is located in Sesvete, on the west side it abuts the Zagreb district of Dubrava, and on its northwest side lies Medvednica. Different microhabitats appear in the researched area: spruce, coniferous, scrub, stream banks and stands of Vinca minor. The vascular flora of this area was investigated from February to November 2022. 114 taxa distributed in 54 plant families were recorded. The most represented plant families are Rosaceae (10%), Compositae (8%), Ranunculaceae (5%), Fabaceae (4%), Scrophulariaceae (4%), Apiaceae (3%), Caryophyllaceae (3%), Juncaceae (3%) and Lamiaceae (3%). The greatest number of species and diversity is in scrubland. The most dominant life forms are long-lived hemicryptophytes (41.23%), geophytes (25.44%) and phanerophytes (19.3%). All microhabitats are dominated by deciduous plants. The dominant forms of propagation are endochory, disochory and myrmecochory. Phytogeographical analysis shows that plants of the Eurasian floral element dominate in the researched area (40.9%). All microhabitats are dominated by plants that correspond to the temperatures of the hilly belt and plants of suboceanic to subcontinental distribution. Eight allochthonous and four invasive species were recorded. According to the Red Book of the Vascular Flora of Croatia, 6 taxa are classified in one of the endangered categories

    An├ílisis de la diversidad flor├şstica y suelos en relaci├│n al impacto del pastoreo en p├íramos herb├íceos de la subcuenca del r├şo San Francisco. Shaglli-Azuay

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    Los p├íramos juegan un papel importante como reguladores h├şdricos y diversas funciones. Su principal amenaza para su deterioro est├í el incremento de ganader├şa en estas zonas, siendo el ganado los principales causantes de la perdida de la diversidad flor├şstica y compactaci├│n del suelo. Estos da├▒os provocados merecen ser evaluados para tomar acciones en su protecci├│n. Se desarroll├│ esta investigaci├│n en los p├íramos de Puculcay y Huertas (Shaglli): teniendo como objetivo estimar la diversidad flor├şstica y el impacto al suelo en p├íramos no intervenidos y en p├íramos intervenidos con pastoreo, para ello se implement├│ 40 parcelas de estudio: 20 en p├íramos no intervenidos y 20 en intervenidos, estos sitios fueron distribuidos en pisos altitudinales de entre 3430 a 4092 m s.n.m. En los sitios de muestreo se tomaron muestras de suelos para determinar Materia Org├ínica (MO), Densidad Aparente (DA), Infiltraci├│n, pH,Conductividad El├ęctrica (CE) y macronutrientes y a su vez se realiz├│ conteo de plantas para determinar diversidad alfa beta y gama y su correlaci├│n. Teniendo resultados de DA en p├íramos no intervenidos 1,183 g/cm3, mientras que en intervenidos 1,508. En el pH ambas zonas presentan suelos ├ícidos con promedios de 4,87. El valor promedio de MO en ambas zonas esde 18,7 siendo suelos con altos contenido de MO. Las 40 parcelas estudiadas presentan valores por debajo de 1 mS/cm en CE. La infiltraci├│n en p├íramos protegidos presenta valores m├ís bajos de 0,25 cmh-1 de. Los resultados de diversidad flor├şstica se obtuvieron 31 especies en p├íramos no intervenidos mientras que en p├íramos intervenidos un total de 35, lo que nos da a conocer una riqueza y abundancia mayor en p├íramos no intervenidos, adem├ís una diversidad beta de un 55 % de similitud en especies entre las dos ├íreas, a su vez una diversidad gamadel 81 % que se encuentra diverso en toda la comunidad estudiada.The paramos play an important role as water regulators and various functions. Its main threat to its deterioration is the increase in livestock in these p├íramos, with lives tock being the main cause of the loss of floristic diversity and soil compaction. These caused damages deserve to be evaluated in order to take actions to protect them. This research was developed in the paramos of Puculcay and Huertas (Shaglli): with the objective of estimating the floristic diversity and the impact on the soil in non- intervened p├íramos and in intervened p├íramos with grazing, for this, 40 study plots were implemented: 20 in non-intervened p├íramos and 20 in intervened, these sites were distributed in altitudinal floors between 3430 to 4092 m a.s.l. Soil samples were taken at the sampling sites to determine Organic Matter (OM), Apparent Density (DA), Infiltration, pH, Electrical Conductivity (EC) and macronutrients, and a t the same time, plant counts were carried out to determine alpha beta and gamma diversity. and its correlation. Having DA results in non-intervened p├íramos 1,183 g/cm3, while in intervened1,508. In the pH, both zones present acidic soils with averages of 4.87. The average OM value in both zones is 18.7, being soils with high OM content. The 40 plots studied show values below 1 mS/cm in CE. Infiltration in protected p├íramos presents lower values of 0.25 cmh-1 de. The results of floristic diversity averages of 20 species were obtained in non- intervened p├íramos while in intervened p├íramos a total of 9, which reveals a greater richness and abundance in non-intervened p├íramos, in addition to a beta diversity of 55% of similarity in species between the two p├íramos, in turn a range diversity of 81% that is diverse throughout the community studied.Ingeniero Agr├│nomoCuenc

    El raro chinche de las marismas Teratocoris antennatus (Boheman, 1852) (Hemiptera, Miridae), nueva especie para Portugal

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    Ria de Aveiro costal lagoon is a socio-ecological system framed between the land and the sea. The lagoon is embedded in a biodiversity rich landscape mosaic comprising beaches, dunes, sandflats, mudflats, seagrasses, and small water channels, and is one of the largest saltmarsh areas in Portugal and in Europe, supporting coastal food webs and providing nursery areas for several species. Despite being a Long-Term Ecological Research (LTER) site and integrating the Natura 2000 network, few systematic studies have been carried on its entomofauna. In this work, field collections were carried in seven locations along Ria de Aveiro saltmarsh areas by sweep-netting the dominating halophyte vegetation in September 2020. From these collections, Teratocoris antennatus (Boheman, 1852), a rare marsh bug, is reported for the first time for Portugal

    Vascular Plants of the Caribou-Targhee National Forest and Curlew National Grassland in Southeastern Idaho, Western Wyoming, and Northern Utah

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    Due to a historical paucity of collections from and the absence of a comprehensive floristic treatment for parts of the Caribou-Targhee National Forest and Curlew National Grassland, an updated inventory for the area was needed. I present an annotated checklist of the vascular plants documented from the Caribou-Targhee National Forest and Curlew National Grassland. A total of new 3189 voucher specimens were collected for this project in 2021 and 2022. To compile the annotated checklist, I consulted both newly collected specimens and specimen data from online botanical databases. A total of 1557 taxa (species, subspecies, varieties, and hybrids), 1423 species (including hybrids), 481 genera, and 94 families are known to occur in the study area. At least three new state records (Draba thompsonii (C.L. Hitchc.) G. Mulligan & Al-Shehbaz, Sphaeralca parvifolia A. Nelson, and Boechera lasiocarpa (Rollins) Dorn) and 137 new county records were documented, a few of which were published previously. An additional 38 first records were discovered, of which approximately 21.1% were not native to the United States. A number of other important occurrences were documented, such as occurrences of rare taxa, Forest Service Region 4 Sensitive Species, and new reports of non-native taxa. The large number of documented county records supports the continued applicability of the Wallacean Shortfall in the flora of western North America. Employees of the U.S. Forest Service, academic researchers, and others will be able to use the annotated checklist to better understand, research, and conserve the flora of the Caribou-Targhee National Forest and Curlew National Grassland

    Pre-Hispanic terrace agricultural practices and long-distance transfer of plant taxa in the southern-central Peruvian Andes revealed by phytolith and pollen analysis

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    The archaeological excavation of two abandoned prehispanic agricultural terraces (Infiernillo and Tocotoccasa) in the Chicha-Soras Valley (Apurimac) in southern-central Peru revealed the presence of palaeosols. The palaeosols represent soil that developed following construction of agricultural terraces during the Middle Horizon. The soil profiles at the current surface developed following reconstruction of the terraces during the Late Intermediate Period. Phytolith analysis revealed an unexpected presence of Arecaceae (palm family) and Marantaceae (arrowroot family) in both terraces, which has been attributed to local cultivation and/or transportation and use of soil, dung, plant material or implements (made of Arecaceae) on the terrace surfaces. Pollen analysis of a nearby wetland (Ayapampa) did not provide evidence for Arecaceae or Marantaceae. Both phytolith and pollen analysis of the terraces and wetland (respectively) indicated that Zea mays was cultivated locally during the Middle Horizon and Late Intermediate Period, although phytoliths of maize are absent from the wetland record during the Middle Horizon. The presence of Solanaceae and Chenopodiaceae/Amaranthaceae pollen in the wetland may be indicative of cultivation of further important taxa during the Middle Horizon and Late Intermediate Period, which continued into the Late Horizon together with Zea mays
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