Hectare in the context of "Czersk, Masovian Voivodeship"

The Axios Delta National Park (Greek: Εθνικό Πάρκο Δέλτα Αξιού), officially the Axios-Loudias-Aliakmonas Delta National Park (Εθνικό Πάρκο Δέλτα Αξιού-Λουδία-Αλιάκμονα), is a national park on the west coast of the Thermaic Gulf in Greece, consisting of multiple wetlands. It covers an area of 33,800 ha and is a Ramsar site, an Important Bird Area and part of the Natura 2000 network.

An old-growth forest or primary forest is a forest that has developed over a long period of time without disturbance. Due to this, old-growth forests exhibit unique ecological features. The Food and Agriculture Organization of the United Nations defines primary forests as naturally regenerated forests of native tree species where there are no clearly visible indications of human activity and the ecological processes are not significantly disturbed. One-third (34 percent) of the world's forests are primary forests. Old-growth features include diverse tree-related structures that provide diverse wildlife habitats that increases the biodiversity of the forested ecosystem. Virgin or first-growth forests are old-growth forests that have never been logged. The concept of diverse tree structure includes multi-layered canopies and canopy gaps, greatly varying tree heights and diameters, and diverse tree species and classes and sizes of woody debris.

As of 2020, the world has 1.11 billion ha (2.7 billion acres) of primary forest remaining. Combined, three countries (Brazil, Canada, and Russia) host more than half (61 percent) of the world's primary forest. The area of primary forest has decreased by 81 million ha (200 million acres) since 1990, but the rate of loss more than halved in 2010–2020 compared with the previous decade.

In archaeology, survey or field survey is a type of field research by which archaeologists (often landscape archaeologists) search for archaeological sites and collect information about the location, distribution and organization of past human cultures across a large area (e.g. typically in excess of one hectare, and often in excess of many km). Archaeologists conduct surveys to search for particular archaeological sites or kinds of sites, to detect patterns in the distribution of material culture over regions, to make generalizations or test hypotheses about past cultures, and to assess the risks that development projects will have adverse impacts on archaeological heritage.

Archaeological surveys may be: (a) intrusive or non-intrusive, depending on the needs of the survey team (and the risk of destroying archaeological evidence if intrusive methods are used) and; (b) extensive or intensive, depending on the types of research questions being asked of the landscape in question. Surveys can be a practical way to decide whether or not to carry out an excavation (as a way of recording the basic details of a possible site), but may also be ends in themselves, as they produce important information about past human activities in a regional context.

Fair Park is a recreational and educational complex in Dallas, Texas, United States, located immediately east of downtown. The 277-acre (112 ha) area is registered as a Dallas Landmark and National Historic Landmark; many of the buildings were constructed for the Texas Centennial Exposition in 1936.

Fair Park has been designated a Great Place in America by the American Planning Association.

Australia has many forests of importance due to significant features, despite being one of the driest continents. As of 2009, Australia has approximately 147 million hectares of native forest, which represents about 19% of Australia's land area. The majority of Australia's trees are hardwoods, typically eucalypts, rather than softwoods like pine. While softwoods dominate some native forests, their total area is judged insufficient to constitute a major forest type in Australia's National Forest Inventory. The Forests Australia website provides up-to-date information on Australia's forests. Detailed information on Australia's forests is available from Australia's State of the Forests Reports that are published every five years.

Tetzcoco (Classical Nahuatl: Tetzco(h)co pronounced [tetsˈkoʔko], Otomi: Antamäwädehe) was a major Acolhua altepetl (city-state) in the central Mexican plateau region of Mesoamerica during the Late Postclassic period of pre-Columbian Mesoamerican chronology. It was situated on the eastern bank of Lake Texcoco in the Valley of Mexico, to the northeast of the Aztec capital, Tenochtitlan. The site of pre-Columbian Tetzcoco is now subsumed by the modern Mexican municipio of Texcoco and its major settlement, the city formally known as Texcoco de Mora. It also lies within the greater metropolitan area of Mexico City.

Pre-Columbian Tetzcoco is most noted for its membership in the Aztec Triple Alliance. At the time of the Spanish conquest of the Aztec Empire, it was one of the largest and most prestigious cities in central Mexico, second only to the Aztec capital, Tenochtitlan. A survey of Mesoamerican cities estimated that pre-conquest Tetzcoco had a population of 24,000+ and occupied an area of 450 hectares.

A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) biome and ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of grasses. Four savanna forms exist; savanna woodland, where trees and shrubs form a light canopy; tree savanna, with scattered trees and shrubs; shrub savanna, with distributed shrubs; and grass savanna, where trees and shrubs are mostly nonexistent.

Savannas maintain an open canopy despite a high tree density. It is often believed that savannas feature widely spaced, scattered trees. However, in many savannas, tree densities are higher and trees are more regularly spaced than in forests. The South American savanna types cerrado sensu stricto and cerrado dense typically have densities of trees similar to or higher than that found in South American tropical forests, with savanna ranging from 800 to 3300 trees per hectare (trees/ha) and adjacent forests with 800–2000 trees/ha. Similarly Guinean savanna has 129 trees/ha, compared to 103 for riparian forest, while Eastern Australian sclerophyll forests have average tree densities of approximately 100 per hectare, comparable to savannas in the same region.