In your blog discuss at least three stressors of an urban environment and choose one resource to focus the majority of your post on. Discuss some of the behavorial and physiological adaptations required for a species of animal or plant access the resource you choose in an urban environment.
By 2030 it is estimated that 60% of the global population will live in a metropolitan setting. Interactions between non-living factors, such as sunlight and water, and biological factors, such as plants and microbes, take place in all environments including cities. Concentrating humans and the resources they consume in metropolitan areas alters such things as soil drainage, water flow, and light availability. For example, sidewalks and rooftops can change an area's hydrology by increasing storm water runoff and can contribute to higher urban temperatures by storing heat energy and acting as an artificial heat sink.Urban ecology does not necessarily make value judgments about whether urban environments are 'good' or 'bad'. Some species of animals such rats, pigeons, and cockroaches, for example, are able to survive and thrive in a non-natural urban setting. Attempting to understand the factors that make some species successful in urban environments while others perish is a common topic of research.
Many of us live in urban environments, but many of the plants and animals that once lived in these areas cannot survive the conditions we have created. Cities are like deserts in many ways. Water storage is one impediment to wildlife in urban areas. The concrete and asphalt that constitute the majority of surfaces in cities do not store water. After rainfall, the water swiftly runs off into sewers, leaving very little for plants to use in between rain events. Secondly, we keep our streets and roofs clean and do not allow soil to form. If you notice, the plants growing in the photos are only growing in cracks where we have inadvertently allowed soil to form from dust and feces and where moisture does not evaporate as quickly. Lastly, like a desert, cities heat up very quickly and then can loose heat very quickly. Any plant that will survive here must be able to tolerate large temperature differences.
ReplyDeletePlants and many life forms near the bottom of the food chain must have soil to survive. Soil must retain moisture, hold nutrients, and provide a substrate for plant roots. These conditions are not met in many places in the city. Plants that are adapted to life in the city must not require deep or very nutritious soils. The grass and the dandilon are two examples of plants that are "pioneers" in the natural world. They can root and survive in very shallow soils with very little precipitation. In general, the plants that can survive the urban environment must be able to survive a wide variety of poor growing conditions.
Without an extensive soil layer, many insects cannot survive in urban areas. The predators that live in urban areas must be generalists. They cannot rely on a steady supply of their natural food source, and must instead be inclined to forage and consume the scraps they can find. Because the base of the food chain is missing in an urban environment, many of the animals that are so prevalent in urban environments are dependant on our waste for survival.