Urban forests
Urbanization & Urban Ecosystems
● Concrete jungles or built environment, the landscape includes places where most of the property is devoted to all things man-made .
● Large concentrations of people and industrial activity that consume more available energy and material than can be produced, and which produce more wastes than can be assimilated with the relatively small area they occupy.
● Urbanization is an important driver of climate change, and pollution alters both biotic and abiotic ecosystem properties within, surrounding, and even at great distances from urban areas (Grimm et al. 2008).
Humans: A Keystone Species
● A keystone species has the capability of altering the abiotic and biotic components of the natural ecosystem as to make them immediately less habitable to some species, more habitable to others, at least for as long as they are present.
● Constructing dispersal barriers & invasion pathways via habitat fragmentation
● Introducing exotic species
● Changing relationships among organisms at different levels.Can reverse such harmful changes by following simple rules!
Taking better care of urban soils?
● Less porosity (restricted aeration)
& compact.
● Restricted water drainage & highly modified soil temperature
● Invites exotic & invasive species
● Atmospheric deposition of pollutants as well as presence of other contaminants & inorganic wastes.
● Modified pH → elevated soil reactions
● Interrupted nutrient cycling.
Golden rules of soil conservation :
• Cover the soil
• Minimal or zero tillage
• Mulch for nutrients
• Maximize biomass production (organic litter deposition + Composting)
• Maximize biodiversity
• Near-neutral pH
• Low salt content
What are Urban Green Spaces?
There are three ecological categories of urban green spaces: remnant, successional, and managed habitat patches.
One example of each is undeveloped natural areas, vacant lots, and cemeteries, respectively.
Urban green spaces should be classified based on ecological characteristics instead of by land use.
The ecological characteristics of urban green spaces select for different assemblages of wildlife species.
The different assemblages of wildlife species in urban green spaces present diverse wildlife management challenges that encourage or discourage their presence.
What are Urban Forests?
Patches of dense green spaces in urban areas filled with native species of plants in small and large areas, serving various purposes, like:
● Edible greens
● Environmental education
● Recreational Spots for nature lovers, observers, enthusiasts and children
● Lungs of the city
● Inspiration for artists, poets and aesthetically pleasing.
● Increases resilience of the city against climate change
● Cooler atmosphere
● Makes people healthier
Urban Forests
Urban forests come in many different shapes and sizes.
They include urban parks, street trees, gardens, river corridors,
wetlands, nature preserves, shelterbelts of trees, and working trees
at former industrial sites.
Urban forests, through planned connections of green spaces, form
the green infrastructure on which communities depend.
Green infrastructure works at multiple scales from the
neighborhood to the metro area to the regional landscape.
BASIC PRINCIPLES GUIDING FOREST CREATION
1. Soil
2. Microclimate
3. Reference sites and basic ecology of the region
4. Vegetation composition and seasonality
5. Species inventories
6. Plantation and Resource competition
7. Succession
8. Native nurseries and help from forest department
9. Management and maintenance (Weeding, Bunds, Pests)
10. Monitoring and comparisons (along time frame) + Corrective measures
Miyawaki method of Afforestation
Miyawaki is a technique pioneered by Japanese botanist Akira Miyawaki, that helps build dense, native forests. It involves planting dozens of native species in the same area, and becomes maintenance-free after the first three years. Mostly used to create tropical forests. Major components include:
a) Soil analysis
b) Soil enrichment
c) Plantation of native species
d) Maintenance