scholarly journals Environmental impacts from human activities affect the diversity of the Odonata (Insecta) in the Eastern Amazon

2021 ◽  
Vol 24 ◽  
pp. 300-315
Author(s):  
R. C. Bastos ◽  
Joás Brito ◽  
Erlane Cunha ◽  
G. M. Cruz ◽  
J. L. S. Pereira ◽  
...  

Land use influences the biodiversity of stream systems by changing the chemical composition of the water and the physical structure of the habitat. The present study evaluated the influence of these processes on the diversity metrics of Odonata at regional and local scales, testing the hypothesis that the two odonate suborders Anisoptera and Zygoptera will respond differently to habitat and landscape variables. The study focused on 13 sites in the municipality of Barcarena, Pará, Brazil. We found no significant impact from regional factors, although anisopterans were more affected by water temperature and Habitat Integrity Index (HII). The HII indicated that the local forest was stable, but anisopteran richness was negatively correlated with HII. It was indicating that these species favoured open areas with less riparian cover. Even though zygopterans did not exhibit a similar systematic pattern, the reduced abundance of Chalcopteryx rutilans, a species associated with better-preserved habitats, may indicate that some sites lack the habitat integrity necessary to establish populations of this species. These findings highlight the importance of preserving the riparian forest to maintain the health of the stream systems. We recommend more studies that focus on the broader geographic and temporal scales to account for factors such as the anthropogenic gradient and historical land use patterns.

1996 ◽  
Vol 18 (1) ◽  
pp. 87-93 ◽  
Author(s):  
P. Sainsbury ◽  
R. Hussey ◽  
J. Ashton ◽  
B. Andrews

2017 ◽  
Vol 8 (4) ◽  
pp. 189-197
Author(s):  
Christiane Cavalcante Leite ◽  
Marcos Heil Costa ◽  
Ranieri Carlos Ferreira de Amorim

The evaluation of the impacts of land-use change on the water resources has been, many times, limited by the knowledge of past land use conditions. Most publications on this field present only a vague description of the past land use, which is usually insufficient for more comprehensive studies. This study presents the first reconstruction of the historical land use patterns in Amazonia, that includes both croplands and pasturelands, for the period 1940-1995. During this period, Amazonia experienced the fastest rates of land use change in the world, growing 4-fold from 193,269 km2 in 1940 to 724,899 km2 in 1995. This reconstruction is based on a merging of satellite imagery and census data, and provides a 5'x5' yearly dataset of land use in three different categories (cropland, natural pastureland and planted pastureland) for Amazonia. This dataset will be an important step towards understanding the impacts of changes in land use on the water resources in Amazonia.


Urban Studies ◽  
2011 ◽  
Vol 48 (14) ◽  
pp. 3107-3124 ◽  
Author(s):  
Geoffrey Meen ◽  
Christian Nygaard

This paper considers the impact of existing land use patterns on housing supply price elasticities in local areas of England, under existing planning policies. The paper demonstrates that, despite common national planning policies, local supply responses to market pressures vary considerably, because of differences in historical land uses. The study area covers the Thames Gateway and Thames Valley, which lie to the east and west of London respectively. However, whereas the latter is one of the wealthiest areas of England, the former includes some of the highest pockets of deprivation and was a government priority area for increasing housing supply. Due to differences in historical land use and geography, the price elasticity in the least constrained area is approximately six times higher than the most constrained.


2005 ◽  
Vol 15 (6) ◽  
pp. 1915-1928 ◽  
Author(s):  
William J. Parton ◽  
Myron P. Gutmann ◽  
Stephen A. Williams ◽  
Mark Easter ◽  
Dennis Ojima

1993 ◽  
Vol 14 (1) ◽  
pp. 25-42 ◽  
Author(s):  
Jordan E. Kerber

Selecting an effective archaeological survey takes careful consideration given the interaction of several variables, such as the survey's goals, nature of the data base, and budget constraints. This article provides justification for a “siteless survey” using evidence from a project on Potowomut Neck in Rhode Island whose objective was not to locate sites but to examine the distribution and density of prehistoric remains to test an hypothesis related to land use patterns. The survey strategy, random walk, was chosen because it possessed the advantages of probabilistic testing, as well as the ease of locating sample units. The results were within the limits of statistical validity and were found unable to reject the hypothesis. “Siteless survey” may be successfully applied in similar contexts where the distribution and density of materials, as opposed to ambiguously defined sites, are sought as evidence of land use patterns, in particular, and human adaptation, in general.


2021 ◽  
Vol 13 (4) ◽  
pp. 631
Author(s):  
Kyle D. Woodward ◽  
Narcisa G. Pricope ◽  
Forrest R. Stevens ◽  
Andrea E. Gaughan ◽  
Nicholas E. Kolarik ◽  
...  

Remote sensing analyses focused on non-timber forest product (NTFP) collection and grazing are current research priorities of land systems science. However, mapping these particular land use patterns in rural heterogeneous landscapes is challenging because their potential signatures on the landscape cannot be positively identified without fine-scale land use data for validation. Using field-mapped resource areas and household survey data from participatory mapping research, we combined various Landsat-derived indices with ancillary data associated with human habitation to model the intensity of grazing and NTFP collection activities at 100-m spatial resolution. The study area is situated centrally within a transboundary southern African landscape that encompasses community-based organization (CBO) areas across three countries. We conducted four iterations of pixel-based random forest models, modifying the variable set to determine which of the covariates are most informative, using the best fit predictions to summarize and compare resource use intensity by resource type and across communities. Pixels within georeferenced, field-mapped resource areas were used as training data. All models had overall accuracies above 60% but those using proxies for human habitation were more robust, with overall accuracies above 90%. The contribution of Landsat data as utilized in our modeling framework was negligible, and further research must be conducted to extract greater value from Landsat or other optical remote sensing platforms to map these land use patterns at moderate resolution. We conclude that similar population proxy covariates should be included in future studies attempting to characterize communal resource use when traditional spectral signatures do not adequately capture resource use intensity alone. This study provides insights into modeling resource use activity when leveraging both remotely sensed data and proxies for human habitation in heterogeneous, spectrally mixed rural land areas.


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