Anthropogenic Island Research Articles

Fern Species-Area Relationship in Urban Anthropogenic Islands in Slawi, Tegal, Central Java

In anthropogenic islands as urban parks, the fern species richness and composition may be determined ecologically by the quality of habitat, including area greenness, or biogeographically by area size. As the development of the theory of island biogeography also includes man-made parks, it is feasible to test whether area-species relationship applies in these urban parks, and is more pronouncedly evident compared to another ecological factor, such as NDVI. Total species number and composition of 8 urban parks in a kecamatan in Tegal Regency were collected and arranged in clustering methods to understand the similarity between parks. The similarity analysis result is important for the management of the parks in Slawi. The species richness data is subsequently tested using Pearson correlation and regression against NDVI and area sizes. The relation between NDVI and species richness is non-significant (p=0.058), while area size and species richness is significant (p=0.003). This signifies that the urban fern species richness is determined by area as biogeographical factor, compared to NDVI as ecological factor. This result is important for the purpose of designing and managing urban parks as evidently size is important in the effort of attracting native biodiversity into urban parks and in turn enhancing the well-being of urban population.

Calusa Fisheries and Estuarine Socio-Ecologies in Southwestern Florida: An Examination of Large-Bodied Fish

ABSTRACT Mound Key (8LL2), a 51 ha anthropogenic island in Estero Bay, Florida, is comprised of a complex arrangement of midden-mounds of various sizes, canals, watercourts, causeways, and other features. Occupied from approximately a.d. 450 through European contact, Mound Key served as the primary center and political capital of an extensive Calusa socioeconomic network whose economy was rooted in fishing, gathering, and hunting. Drawing on zooarchaeological analyses of ichthyological refuse dating to between a.d. 1000 and 1350, I argue that the Calusa actively managed and invested in a core fishery that ultimately contributed to a complex, robust socio-ecological systems (SES). I examine the nature, role, and signatures of these fisheries, as their management underwrote the success of Calusa social, political, and economic systems.

Considering Urbanism at Mound Key (Caalus), the capital of the Calusa in the 16th Century, Southwest Florida, USA

In 1566, Pedro Menéndez de Avilés arrived at Mound Key, the capital of the Calusa polity. What he saw there was unlike anything else he would encounter in La Florida, a capital teaming with people and complex architecture that was essentially a terraformed anthropogenic island constructed mostly of mollusk shells situated in the middle of Estero Bay. The Calusa literally raised this landscape—51 ha in area—from the sea and built a complex canal system to the capital’s interior. The capital and its outlying towns did not practice large-scale agriculture, but rather relied upon harvesting and management of aquatic resources. Here, I outline the nature of urban processes at the settlement. From this evaluation, I argue that there are many similarities between the settlement and other urban areas of research, particularly in other parts of the Americas. I explore how the occupants of Mound Key worked through some of the experiences of urban processes present via collective action, specifically regarding waste management, transparent governance, and sustainability.

Productivity and Nestling Mortality for Three Species of Herons at Natural and Anthropogenic Islands

Productivity and Nestling Mortality for Three Species of Herons at Natural and Anthropogenic Islands

Height differentiation of valley-river landscapes of the right-bank Ukraine

The aim of the article. To analyze the peculiarities of height differentiation of valley-river landscapes and to study their current structure taking a model region as an example – a plain territory of the Right-bank Ukraine. Methods. The study is based on the ideas of F. M. Milkov on anthropogenic landscapes and their vertical (height) differentiation. In the process of research the constructive-scientific landscape approach and the principles of complexity and natural-anthropogenic combination were used. The main research methods, in addition to field, are methods of theoretical generalization, historical and landscape, the leading factor, zoning, modeling, analogy and more. Scientific novelty. The main focus of scientists is only on the impact of vertical zonation on mountain landscapes. Height differentiation of valley-river landscapes has not been given due attention. This is especially true of river valley landscapes that have been transformed as a result of economic activity. Practical value. Previous experience in the optimization of anthropogenic landscapes shows that taking into account their height differentiation is a necessary condition for the development of various projects and schemes of environmental management. Given the growing anthropogenic pressure on the environment, such studies will help to better understand the course of negative man-made processes and contribute to the optimization, conservation and protection of modern valley and river landscapes. In the long run, this may be the basis for similar research in river valleys around the world. Research results. The development of height differentiation within the boundaries of valley-river landscapes of the Right-bank Ukraine was considered based on the earlier experience. 2 height-landscape levels (“young” accumulative and “typical” accumulative-denudation) and 4 tiers were singled out in river valleys. Bridges, dams, causeways, derivative HES, “water” mills, anthropogenic islands, ponds of a riverbed type or meliorative canals – all these are typical for a lower tier of a “young” accumulative height-landscape level. A middle tier is represented with water-economic and agricultural landscapes. An upper tier is formed with residential and mining-industrial landscapes. In river valleys a “typical” accumulative-denudation height-landscape level has one lower tier which is formed with two natural types of localities: sloping and canyon-like. This tier is characterized with a good preservation (up to 35%) of natural landscapes. Anthropogenic landscapes are represented mainly with forest-cultural, residential, agricultural and road landscape complexes. The conclusion has been made that with further anthropogenization of river valleys it is expedient to make designs of anthropogenic landscapes, distributing them on height-landscape teirs evenly and thoughfully. Within the boundaries of a “young” accumulative height-landscape level it advisable to carry out the restoration and optimization of water-economic landscape-technical systems which are at the “aging” stage. To preserve valley-river landscapes it should be forbidden to take any economic measures except for the optimization ones.

Late Pleistocene/Early Holocene sites in the montane forests of New Guinea yield early record of cassowary hunting and egg harvesting

How early human foragers impacted insular forests is a topic with implications across multiple disciplines, including resource management. Paradoxically, terminal Pleistocene and Early Holocene impacts of foraging communities have been characterized as both extreme-as in debates over human-driven faunal extinctions-and minimal compared to later landscape transformations by farmers and herders. We investigated how rainforest hunter-gatherers managed resources in montane New Guinea and present some of the earliest documentation of Late Pleistocene through mid-Holocene exploitation of cassowaries (Aves: Casuariidae). Worldwide, most insular ratites were extirpated by the Late Holocene, following human arrivals, including elephant birds of Madagascar (Aepyornithidae) and moa of Aotearoa/New Zealand (Dinornithiformes)-icons of anthropogenic island devastation. Cassowaries are exceptional, however, with populations persisting in New Guinea and Australia. Little is known of past human exploitation and what factors contributed to their survival. We present a method for inferring past human interaction with mega-avifauna via analysis of microstructural features of archaeological eggshell. We then contextualize cassowary hunting and egg harvesting by montane foragers and discuss the implications of human exploitation. Our data suggest cassowary egg harvesting may have been more common than the harvesting of adults. Furthermore, our analysis of cassowary eggshell microstructural variation reveals a distinct pattern of harvesting eggs in late ontogenetic stages. Harvesting eggs in later stages of embryonic growth may reflect human dietary preferences and foraging seasonality, but the observed pattern also supports the possibility that-as early as the Late Pleistocene-people were collecting eggs in order to hatch and rear cassowary chicks.

Seeing Sansha: The Political Aesthetics of a South China Sea Settlement

AbstractOn 24 July 2012, the Sansha People’s Government was established on an anthropogenic island in the South China Sea, more than 350 kilometers from the southernmost point of Hainan Province. S...

Ecological traits modulate bird species responses to forest fragmentation in an Amazonian anthropogenic archipelago

AbstractAimWe assessed patterns of avian species loss and the role of morpho‐ecological traits in explaining species vulnerability to forest fragmentation in an anthropogenic island system. We also contrasted observed and detectability‐corrected estimates of island occupancy, which are often used to infer species vulnerability.LocationTucuruí Hydroelectric Reservoir, eastern Brazilian Amazonia.MethodsWe surveyed forest birds within 36 islands (3.4–2,551.5 ha) after 22 years of post‐isolation history. We applied species–area relationships to assess differential patterns of species loss among three data sets: all species, forest specialists and habitat generalists. After controlling for phylogenetic non‐independence, we used observed and detectability‐corrected estimates of island occupancy separately to build competing models as a function of species traits. The magnitude of the difference between these estimates of island occupancy was contrasted against species detectability.ResultsThe rate of species loss as a function of island area reduction was higher for forest specialists than for habitat generalists. Accounting for the area effect, forest fragmentation did not affect the overall number of species regardless of the data set. Only the interactive model including natural abundance, habitat breadth and geographic range size was strongly supported for both estimates of island occupancy. For 30 species with detection probabilities below 30%, detectability‐corrected estimates were at least tenfold higher than those observed. Conversely, differences between estimates were negligible or non‐existent for all 31 species with detection probabilities exceeding 45.5%.Main conclusionsPredicted decay of avian species richness induced by forest loss is affected by the degree of habitat specialisation of the species under consideration, and may be unrelated to forest fragmentation per se. Natural abundance was the main predictor of species island occupancy, although habitat breadth and geographic range size also played a role. We caution against using occupancy models for low‐detectability species, because overestimates of island occupancy reduce the power of species‐level predictions of vulnerability.

Island extinctions: processes, patterns, and potential for ecosystem restoration

SUMMARYExtinctions have altered island ecosystems throughout the late Quaternary. Here, we review the main historic drivers of extinctions on islands, patterns in extinction chronologies between islands, and the potential for restoring ecosystems through reintroducing extirpated species. While some extinctions have been caused by climatic and environmental change, most have been caused by anthropogenic impacts. We propose a general model to describe patterns in these anthropogenic island extinctions. Hunting, habitat loss and the introduction of invasive predators accompanied prehistoric settlement and caused declines of endemic island species. Later settlement by European colonists brought further land development, a different suite of predators and new drivers, leading to more extinctions. Extinctions alter ecological networks, causing ripple effects for islands through the loss of ecosystem processes, functions and interactions between species. Reintroduction of extirpated species can help restore ecosystem function and processes, and can be guided by palaeoecology. However, reintroduction projects must also consider the cultural, social and economic needs of humans now inhabiting the islands and ensure resilience against future environmental and climate change.

Archaeology, historical ecology and anthropogenic island ecosystems

In the face of environmental uncertainty due to anthropogenic climate change, islands are at the front lines of global change, threatened by sea level rise, habitat alteration, extinctions and declining biodiversity. Islands also stand at the forefront of scientific study for understanding the deep history of human ecodynamics and to build sustainable future systems. We summarize the long history of human interactions with Polynesian, Mediterranean, Californian and Caribbean island ecosystems, documenting the effects of various waves of human settlement and socioeconomic systems, from hunter–gatherer–fishers, to agriculturalists, to globalized colonial interests. We identify degradation of island environments resulting from human activities, as well as cases of human management of resources to enhance productivity and create more sustainable systems. These case studies suggest that within a general global pattern of progressive island degradation, there was no single trajectory of human impact, but rather complex effects based on variable island physiographies, human subsistence strategies, population densities, technologies, sociopolitical organization and decision-making.

Archaeology, historical ecology and anthropogenic island ecosystems

SUMMARYIn the face of environmental uncertainty due to anthropogenic climate change, islands are at the front lines of global change, threatened by sea level rise, habitat alteration, extinctions and declining biodiversity. Islands also stand at the forefront of scientific study for understanding the deep history of human ecodynamics and to build sustainable future systems. We summarize the long history of human interactions with Polynesian, Mediterranean, Californian and Caribbean island ecosystems, documenting the effects of various waves of human settlement and socioeconomic systems, from hunter–gatherer–fishers, to agriculturalists, to globalized colonial interests. We identify degradation of island environments resulting from human activities, as well as cases of human management of resources to enhance productivity and create more sustainable systems. These case studies suggest that within a general global pattern of progressive island degradation, there was no single trajectory of human impact, but rather complex effects based on variable island physiographies, human subsistence strategies, population densities, technologies, sociopolitical organization and decision-making.

Nuclear and Plastid DNA Sequence-based Molecular Phylogeography of Salvadora oleoides (Salvadoraceae) in Punjab, India Reveals Allopatric Speciation in Anthropogenic Islands Due to Agricultural Expansion

Salvadora oleiodes is a tropical tree species belonging to the little-known family Salvadoraceae and distributed in the arid regions of Africa and Asia. Aims of our study were to trace the microevolutionary legacy of this tree species with the help of sequence-based multi-local phylogeography and to find the comparative placement of family Salvadoraceae within angiosperm clade malvids. A total 20 geographical isolates were collected from different regions of North India, covering a major part of its species range within the Indian Subcontinent. Sequence data from nuclear-encoded Internal Transcribed Spacer region (ITS1-5.8S-ITS2) and plastid-encoded trnL-F spacer region, were generated for this species for the first time in the world. ITS-based Bayesian phylogeographic analysis revealed the existence of four clades while trnL-F spacer based Bayesian analysis revealed one clade for this species distributed in the Indian subcontinent. Between these two loci, ITS revealed more distinct phylogeographic clades, indicating the phylogeographic utility of this locus for the systematics of Salvadoraceae. Interestingly, the ITS phylogeny indicated the existence of allopatric speciation in this tree species. Factors such as habitat destruction through agricultural expansion of plains might have forced the remaining population of this threatened tree species to isolated patches of thorn forest biotas, the ‘anthropogenic islands’, analogous to an archipelago. Phylogenetic analyzes based on trnL-F spacer suggested a synonymy of this species with Salvadora angustifolia. Maximum Likelihood gene tree based on ITS sequence data revealed that Salvadoraceae belongs to Sapindales rather than Brassicales. However, in the gene tree based on trnL-F spacer sequence, this family clustered within Brassicales. An evolutionary congruence of S. oleoides isolates across its range in North India is revealed in this study. Given the conflicting results on the relative placement of Salvadoraceae in Brassicales and Sapindales, the need for further phylogenetic analyses of malvids using supermatrix approach is highlighted.

From Shell Midden to Midden-Mound: The Geoarchaeology of Mound Key, an Anthropogenic Island in Southwest Florida, USA.

Mound Key was once the capital of the Calusa Kingdom, a large Pre-Hispanic polity that controlled much of southern Florida. Mound Key, like other archaeological sites along the southwest Gulf Coast, is a large expanse of shell and other anthropogenic sediments. The challenges that these sites pose are largely due to the size and areal extent of the deposits, some of which begin up to a meter below and exceed nine meters above modern sea levels. Additionally, the complex depositional sequences at these sites present difficulties in determining their chronology. Here, we examine the development of Mound Key as an anthropogenic island through systematic coring of the deposits, excavations, and intensive radiocarbon dating. The resulting data, which include the reversals of radiocarbon dates from cores and dates from mound-top features, lend insight into the temporality of site formation. We use these insights to discuss the nature and scale of human activities that worked to form this large island in the context of its dynamic, environmental setting. We present the case that deposits within Mound Key’s central area accumulated through complex processes that represent a diversity of human action including midden accumulation and the redeposition of older sediments as mound fill.

Anthropogenic Islands in the Arid West: Comparing the Richness and Diversity of Insect Communities in Cultivated Fields and Neighboring Wildlands

The interface between cultivated fields and wildlands has become a central focus for conservation biology, particularly as previously uncultivated lands worldwide are converted to agriculture at an escalating pace. Although research in some parts of the world has highlighted the potential value of agricultural lands for managing and preserving native animals, we know comparatively little about native animals spanning the cultivated/wildlands interface in North America. The study reported here investigated insect communities at three sets of paired sites (cultivated alfalfa fields and native, sagebrush areas) on the western edge of the Great Basin. Two hundred ninety-nine morphospecies were sorted from a collection of >9,000 insects: 221 morphospecies were found in cultivated fields, and 143 were found in the native areas. Insect communities in alfalfa fields were higher in species richness and abundance than communities in adjacent, native fields. However, communities in the cultivated habitat were relatively more homogenous: species composition was more similar among cultivated fields than among native fields. Considering the number of individual insects and morphospecies found in the cultivated habitat, and the relatively small number of species that overlap the two habitat types, the potential ecological consequences of the widespread, anthropogenic habitat are discussed.