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Waterhole detection using a vegetation index in desert bighorn sheep (Ovis canadensis cremnobates) habitat

Jonathan Gabriel Escobar Flores (2019, [Artículo])

In arid ecosystems, desert bighorn sheep are dependent on natural waterholes, particularly in summer when forage is scarce and environmental temperatures are high. To detect waterholes in Sierra Santa Isabel, which is the largest area of desert bighorn sheep habitat in the state of Baja California, Mexico, we used the normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) from Sentinel-2 satellite images. Waterhole detection was based on the premise that sites with greater water availability, where NDVI was higher, can be identified by their density of vegetation greenness. For the detected waterholes, we estimated the escape terrain (presence of cliffs or steep, rocky slopes) around each by the vector ruggedness measure to determine their potential use by desert bighorn sheep based on the animals’ presence as documented by camera traps. We detected 14 waterholes with the NDVI of which 11 were known by land owners and 3 were unrecorded. Desert bighorn were not detected in waterholes with high values of escape terrain, i.e., flat areas. Waterhole detection by NDVI is a simple method, and with the assistance and knowledge of the inhabitants of the Sierra, it was possible to confirm the presence each waterhole in the field. © 2019 Escobar-Flores et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Article, bighorn sheep, environmental aspects and related phenomena, environmental parameters, habitat, Mexico, nonhuman, normalized difference vegetation index, normalized difference water index, water availability, waterhole, animal, bighorn sheep, CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS CIENCIA FORESTAL CIENCIA FORESTAL

Movements of scalloped hammerhead sharks (Sphyrna lewini) at Cocos Island, Costa Rica and between oceanic islands in the Eastern Tropical Pacific

Elena Nalesso (2019, [Artículo])

Many species of sharks form aggregations around oceanic islands, yet their levels of residency and their site specificity around these islands may vary. In some cases, the waters around oceanic islands have been designated as marine protected areas, yet the conservation value for threatened shark species will depend greatly on how much time they spend within these protected waters. Eighty-four scalloped hammerhead sharks (Sphyrna lewini Griffith & Smith), were tagged with acoustic transmitters at Cocos Island between 2005–2013. The average residence index, expressed as a proportion of days present in our receiver array at the island over the entire monitoring period, was 0.52±0.31, implying that overall the sharks are strongly associated with the island. Residency was significantly greater at Alcyone, a shallow seamount located 3.6 km offshore from the main island, than at the other sites. Timing of presence at the receiver locations was mostly during daytime hours. Although only a single individual from Cocos was detected on a region-wide array, nine hammerheads tagged at Galapagos and Malpelo travelled to Cocos. The hammerheads tagged at Cocos were more resident than those visiting from elsewhere, suggesting that the Galapagos and Malpelo populations may use Cocos as a navigational waypoint or stopover during seasonal migrations to the coastal Central and South America. Our study demonstrates the importance of oceanic islands for this species, and shows that they may form a network of hotspots in the Eastern Tropical Pacific. © 2019 Nalesso et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

article, Cocos Island, human, monitoring, nonhuman, resident, shark, South America, animal, Costa Rica, environmental protection, island (geological), movement (physiology), physiology, season, shark, Animals, Conservation of Natural Resources, Costa CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA

Shopping centers at zmcm. The companies, location and production of a neoliberal urban space

Dante-Guillermo Celis-Galindo (2021, [Artículo, Artículo])

This work aims to analyze different aspects of shopping center at the Metropolitan Zone of Mexico City as location, opening year and developer company. Also it will identify diverse characteristics, economic and political phases in the country as well as the role of the development companies and shopping centers as a producers of a neoliberal urban space. This paper presents the way shopping centers importance has growth and how it had become in a neoliberal city characteristic; with this the characteristics of these urban works are visualized and related with their construction companies and local governments which has caused the transformation of the city. After conducting a census, with more than two hundred shopping centers, the study was delimited to those with the greatest significance by size, location and developer. At the beginning of the paper, the characteristics that shopping malls should have for the realization of this work are mentioned. In a first section an approach is made to the theoretical elements of the city and the shopping center and therefore identifying the developers that most  nfluence this process; the second section addresses the characteristics of places by location and the characteristics that urban planners have depending on the area where they are; the third section discusses the years of opening, the squares and relates to government administrations and the economic characteristics of the country; and finally, a tour of the urban regulations in Mexico City and its latest modifications is made.

shopping center neoliberalism space urban space construction company centro comercial neoliberalismo espacio espacio urbano empresa constructora HUMANIDADES Y CIENCIAS DE LA CONDUCTA HUMANIDADES Y CIENCIAS DE LA CONDUCTA

Addressing agricultural labour issues is key to biodiversity-smart farming

Thomas Daum Frédéric Baudron Matin Qaim Ingo Grass (2023, [Artículo])

There is an urgent need for agricultural development strategies that reconcile agricultural production and biodiversity conservation. This is especially true in the Global South where population growth is rapid and much of the world's remaining biodiversity is located. Combining conceptual thoughts with empirical insights from case studies in Indonesia and Ethiopia, we argue that such strategies will have to pay more attention to agricultural labour dynamics. Farmers have a strong motivation to reduce the heavy toil associated with farming by adopting technologies that save labour but can negatively affect biodiversity. Labour constraints can also prevent farmers from adopting technologies that improve biodiversity but increase labour intensity. Without explicitly accounting for labour issues, conservation efforts can hardly be successful. We hence highlight the need for biodiversity-smart agriculture, that is farming practices or systems that reconcile biodiversity with land and labour productivity. Our empirical insights suggest that technological and institutional options to reconcile farmers' socio-economic goals and biodiversity conservation exist but that more needs to be done to implement such options at scale.

Land Sharing Trade-Offs CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA AGRICULTURAL DEVELOPMENT BIODIVERSITY CONSERVATION LABOUR SUSTAINABILITY