Private Urban Greenspaces or “Patios” as a Key Element in the Urban Ecology of

Tropical Central America

Presented by Shannon Slivinske

The urban ecology of patio-gardens are valuable in connecting the environment with urban green

space and quality of life.Increasing interest factors: climate change exotics/invasives habitat/wildlife conservation sustainability

Study Area

Leon, West NicaraguaFounded 1610Adjacent to indigenous Sutiaba settlementAltitude 109 mDry tropical climate1385 mm annual rain, peak between May & Oct.27°C, varying +/- 3° yearly

Indigenous sp. Found in Patios

Common forest sp.:

Bursera simaruba,

Calycophyllum candidissimum

Ceiba pentrandra.

Common tree and bush sp. of degraded area:

Pithecellobium dulce

Gliricidia sepium

Byrsonima crassifolia

Crescentia alata

Patios are a Basic Element of Leon Dwellings

Hypothesis

1. urban plant diversity reflects cultural and historical processes

2. urban plant diversity independent of historical dynamics, depends on individual

Additional implications:- Ecological functioning and resource provisions

- Reservoir for native species/resource patch/corridor

- Microclimate/climate control for inner-city dwellings

53 houses in July-Sept. '01

30 houses in July-Sept. '02

Total houses: 83

Total patios: 96

Patio vegetation floristic/structural composition

Patio structure and management

Categorized by plant species, diversity and rarity indicies

Methods and Data

Results

293 spp. Mean richness: 26.21 Standard deviation: 19.77 Half = < 6 patios 80% tropical 37.54% native 57.67% exotic

Composition, Diversity and Structure

Colonial and transitional- greatest sp./area, little spontaneous

Indigenous- greatest sp. richness, spontaneous (or self-seeded) and rare

Recent- greatest diversity but lowest richness and sp./area, high spontaneity

Common Species

Species Mean and Percentage

No significant difference in plant cover except:

Colonials having no understory trees (5-15m)

Indigenous having majority of canopy trees (15m+)

and more than half of their overall species are woody

Human Management Variables

Colonial- Center of historical district Corridors (microclimate and

air circulation)

Transitional- Colonial in poorer state Peripheral to historical

Indigenous- Neighboring village Lowest architectural complexity Highest garden-patio area

Recent- City outskirts Low economic power Cheap, small housing

Main Uses

Linear Elements

Indigenous Patio-Gardens

-Preserved original structure and floristic composition variably -Ecological/ethnobotanical diversity

-Complex agroforestry, dry tropical forest

Closest: Ornamentals, herbaceous, spices, medicinals, small bushes/palms (irrigated)

Farther: Fruit trees & interplanted timber treesFarthest: Spontaneous

Conclusion

Indigenous patios-- sustainable agroforestry systems:

60 sp. rich- substantial diversitysoil conservation (erosion, fertility)microclimateendogenous inputsprovides alternative or extra incomewater consciousPAR interception

socializationhealth benefits

Colonial patios-- historical and ecological:

Architectural microclimate

outstanding mature tree specimens frequent uncommon species40 sp. Rich (higher diversity)

Patios in urban environments are of ecological importance both to humans and surrounding

environment and in enhancing quality of life with personal green space.

Works Cited

Molles, Manuel C. Jr., 2008. Species Diversity. Ecology: Concepts and Applications 4th ed., 373-374.

Torquebiau, Emmanuel, 1992. Are Tropical Agroforestry Home Gardens Sustainable? Agric. Ecosystems Environ., 41 : 189-207.

Fernandes, E. C. M. and P. K. R. Nair, 1986. An Evaluation of the Structure and Function of Tropical Homegardens. Agric. Systems, 21: 279-310.