Landscape based conservation

• Natural landscape/protective landscape – forest/wildlife ecology
• Productive landscape – rural ecology
• Built or urban landscape – urban ecology

Urban landscape

• Built area – buildings, roads, drainage etc
• Open green space such as public parks Landscape and level of modification
• Street trees and home gardens
• Water bodies – ponds, rivers
• Urban ecosystems differ with natural one in several respects: in climate, soil, hydrology, species composition, population dynamics, flow of energy and matters.

What is Urban Ecology?

• Urban Ecology is the study of ecosystems that include humans living in cities and urbanizing landscapes.
• The application of the principles of ecology to a study of urban environments.
• The term “urban ecology” has been used variously to describe the study of humans in cities, of nature in cities, and of the coupled relationships between humans and nature.
• Urban ecology is the study of the co-evolution of human-ecological systems
• It is an emerging, interdisciplinary field that aims to understand how human and ecological processes can coexist in human-dominated systems and help societies with their efforts to become more sustainable.
• "Ecology of cities" and "ecology in cities"

History of urban ecology

• It flourished in the 1920s and 1930s, went through a period of neglect.
• It was revived in the late 1950s and early 1960s
• Interest is growing but it is still not seen as central in conservation studies.

Why Urban Ecology

• Human alteration of Earth is substantial and growing. Between one-third and one-half of the land surface has been transformed by human action.
• The future of Earth‟s ecosystems is increasingly influenced by the pace and patterns of urbanization.
• Cities are both drivers of, and driven by, ecological processes within and beyond their boundaries.
• Urbanization change natural habitat and species composition alters hydrological cycle and modifies nutrient cycles and energy flow.

Urban population trend

• Urban population will reach 60% by the year 2030 (4.9 billion).
• Just over half the world now lives in cities but by 2050, over 70% of the world will be urban dwellers.
• By 2050, only 14% of people in rich countries will live outside cities, and 33% in poor countries.
• Nepal has now 58 urban centers located in various districts of Nepal with a total urban population 14 per cent in 2001 which will be nearly 50% by 2050.
• Nepal's urban centers increased from 16 in 1971, 23 in 1981, 33 in 1991 and 58 in 2001.
• By 2050, most of the population growth expected in urban areas will be concentrated in the cities and towns of the less developed regions. Asia, in particular, is projected to see its urban population increase by 1.8 billion, Africa by 0.9 billion, and Latin America and the Caribbean by 0.2 billion.

Global urban and rural populations trend (1950-2050)

Importance of urban ecology

• Urban development produces some of the greatest local extinction rates and frequently eliminates the large majority of native trees.
• Understanding how urban ecosystems function is integral to mitigating their negative effects on ecosystem services, the study of the relationship between organisms and environment.
• Interest has been growing about sustainable urban landscapes and the conservation of indigenous vegetation within urban environments.
• Study of UE helps develop the management of healthy and biodiverse urban ecosystems.
• Quality in the urban environment will also lead to long-term social gains.

Urban ecology

• Urban ecology is a new branch of environmental studies that seeks to understand the natural systems of urban areas and the threats that face them.
• Urban ecologists study the trees, rivers, wildlife and open spaces found in cities to understand the extent of those resources and the way they are affected by pollution, over-development and other pressures.
• The term is also applied to the sum of societal relations with nature, and the restoration of non-human nature in cities.

Various aspects of Urban Ecology

1. Ecology and evolution of organisms that happen to live within city boundaries;
2. Biological, political, economic, and cultural ecology of Homo sapiens in urban settings;
3. Cities as emergent phenomena of coupled human and natural processes with implications for evolution and survival of our own and other species.
4. Most studies in urban ecosystems focus on individuals, populations, or communities of plants and animals, while studies of urban ecosystems typically focus on ecosystem-level processes like nutrient cycling and energy flow.
5. Human factors are not isolated from other biotic or abiotic factors - together, as coupled human-natural systems; they both drive and are affected by the patterns and processes they create.
6. Urban ecology has been criticized for focusing too much on competition at the expense of the cultural and subjective forces which shape the city.
7. Needs to take into account the dynamic and heterogeneous physical and social characteristics of an urban ecosystem.

Urban adaptation

• Buildings and quarries act as cliffs for nesting and roosting birds;
• Street lamps, telegraph poles and pylons provide perching sites;
• Cellars and roof spaces substitute as caves for bats;
• Although species in urban sites are not usually unique, they may form interesting communities which exploit the special conditions in these disturbed environments.
• Novel combinations of characteristics lead to some urban sites having a high nature conservation value: in 1990 nearly 30 per cent of all Sites of Special Scientific Interest (SSSI) in England were classed as urban or urban fringe.
• Large and less tolerant mammals cannot adapt in urban areas
• In many cases, native species have given way to exotic species, especially along streets and in urban parks.

The physical, ecological and geographical make up of urban sites influence the species

Urban green and green space

• Urban green space is vital for the inhabitants of urban areas, because it provides benefits as recreational and educational opportunities, aesthetic experiences – not to mention human health benefits.
• The biodiversity of urban green spaces is essential for the provision of ecosystem services. Moreover, habitats and species in urban green space can have significant conservation values, as rare and endangered species are often encountered in urban green space.
• In order to sustain biodiversity and maintain the provision of ecosystem services in urban areas, it is vital to conserve habitats of adequate size and ecological quality.
• To accomplish the conservation of biological diversity and ecosystem services, it is necessary to incorporate ecological information into land-use planning as well as green space planning and management.
• Urban ecology helps understand structure, function and planning of urban ecosystems and lead to ways of sustainably managing and maintaining urban ecosystems while increasing quality of life for people living in urban areas.

Urban forestry

• Urban forests play a fundamentally important role in building ecological cities.
• Urban forests improve the environmental quality of the urban environment and the aesthetics of urban landscapes, and in many developed and developing countries,
• Urban forestry has been recognized as an essential means of maintaining urban ecosystem health, improving human living conditions, fostering a harmonious human-nature relationship, and ultimately achieving urban sustainability.
• Local authorities in Canberra have planted 400,000 trees to regulate microclimate, reduce pollution and thereby improve urban air quality, reduce energy costs for air conditioning as well as store and sequester carbon.
• These benefits are expected to amount to some US$ 20-67 million over the period 2008-2012, in terms of the value generated or savings realized for the city.