Heritage trees and landscape design in urban areas of Rwanda

Abstract

Trees play a key role in neighborhood landscapes, a belief that has been widely held for millennia in areas beyond Sub-Saharan Africa. Unfortunately, awareness of modern landscape architecture was almost absent in Rwanda until the late 20th century. Today, houses with surrounding decorative and amenity plants are a common feature in Rwanda’s neighborhood landscapes and, as the villagization of settlements progresses, new kinds of landscapes are emerging. This paper explores neighborhood tree planting around human settlements in the country. Remote sensing, photogrammetry, photo interpretation, and plant surveys were the core methods used. The average tree cover fraction ranged between 10%–35%. As the result of what is hereafter referred to as the “luxury effect,” a discrete gradient was detected along which the diversity of ornamental and amenity trees increases with the socio-economic status of neighborhoods: from rural settlements to urban residences via a series of intermediate designs, in which different levels of human-built vegetated areas alternate with non-landscaped spaces. Showy, non-productive amenity trees tend to occur more in wealthy quarters of the inner core of cities while edible ornamentals and other productive neighborhood trees prevail in rural and spontaneous settlements. In general, the practice of landscape plant design, in spite of its constant improvement, is still striving to get established as a profession in the country.

Keywords

heritage trees / patterns / settlement neighborhoods, Rwanda

References

[1] Alem S, Woldemariam T, Pavlis J. Evaluation of soil nutrients under Eucalyptus grandis plantation and adjacent sub-montane rain forest. Journal of Forestry Research, 2010, 21: 457-460.

[2] Balasubramanian V, Egli A. The role of agroforestry in the farming systems in Rwanda with special reference to the Bugesera-Gisaka-Migongo (BGM) region. Agroforestry Systems, 1986, 4: 271-289.

[3] Bloesch U, Troupin G, Derungs N. Les plantes ligneuses du Rwanda: Flore, Ecologie et Usages. 2009, Netherlands: Shaker Velag, 757.

[4] Carfagna E, Gallego FJ. Using remote sensing for agricultural statistics. International Statistical Review, 2005, 73: 389-404.

[5] Christudason A. Optimisation of land use through innovative legislation in Singapore. 2005, Brisbane, Australia: Pacific Rim Real Estate Conference

[6] Department of State. Background Note: Rwanda, 2011

[7] Elzinga CL, Salzer DW, Willoughby JW, Gibbs JP. Monitoring plant and animal populations. 2001, Massachusetts: Blackwell Science Inc

[8] FAO. Tree growing by rural people. Forestry Paper 64, 1985

[9] FAO. Irrigation en Afrique en chiffres: Rwanda. Enquête Aquastat, 2005, 29: 1-8.

[10] Folega F, Huang HG, Zhao XH, Seburanga JL. Urban area vegetation changing assessment over the last 20 years based on NDVI — City of Lomé, Togo. Energy Procedia, 2011, 11: 2449-2454.

[11] Hope D, Gries C, Zhu W, Fagan WF, Redman CL, Grimm NB, Nelson AL, Martin C, Kinzig A. Socioeconomics drive urban plant diversity. PNAS, 2003, 100: 8788-8792.

[12] Jaenson R, Bassuk N, Schwager S, Headley D. A statistical method for the accurate and rapid sampling of urban street tree populations. Journal of Arboriculture, 1992, 18: 171-183.

[13] Janick J. Plant exploration: From Queen Hatshepsut to Sir Joseph Banks. HortScience, 2007, 42(2): 191-196.

[14] Jim CY, Chen WY. Ecosystem services and valuation of urban forests in China. Cities, 2009, 26: 187-194.

[15] Konijnendijk CC, Sadio S, Randrup TB. Urban and peri-urban forestry in a development context: Strategy and implementation. Journal of arboriculture, 2004, 30: 269-276.

[16] Liu E, Wu J, Lee J. Optimization of land use. 1997, Hongkong: Research and Library Services Division Legislative Council Secretariat

[17] Lovell ST. Multifunctional urban agriculture for sustainable land use planning in the United States. Sustainability, 2010, 2: 2499-2522.

[18] Minecofin. Rwanda Vision 2020. 2000, Kigali, Republic of Rwanda: Ministry of Economy and Finance

[19] Mininfra. Kigali conceptual master plan existing conditions analysis. 2007, Kigali, Rwanda: Master Plan, Edaw

[20] Ndayambaje JD, Heijman WJM, Mohren GMJ. Household Determinants of Tree Planting on Farms in Rural Rwanda. Small-scale Forestry, 2012, 11(4): 477-508.

[21] Ndayambaje JD, Mohren GMJ. Fuelwood demand and supply in Rwanda and the role of agroforestry. Agroforestry Systems, 2011, 83: 303-320.

[22] Niskanen A. Value of external environmental impacts of reforestation in Thailand. Ecological Economics, 1998, 26: 287-297.

[23] Prakash J. History of flowers and gardening in India, 2010

[24] Sano JC. Urban environmental infrastructure in Kigali City Rwanda: Challenges and opportunities for modernized decentralized sanitation systems in poor neighborhoods. 2007, Netherlands: Wageningen University

[25] Seburanga JL, Zhang QX. Green infrastructure and amenity plant diversity in urban centers of Rwanda and South China. 2011 International Federation for Landscape Architecture (IFLA) Africa Symposium, JKUAT, Nairobi, Kenya, 2011

[26] Seburanga JL. Ornamental plant diversity in urban centers of Rwanda and South China. 2011, P. R. China: Beijing Forestry University

[27] Singh VS, Pandey DN, Chaudhry P. Urban forests and open green spaces: Lessons of Jaipur, Rajastahn, India. RSPCB, 2010, 1: 1-23.

[28] Smith RM, Thompson K, Hodgson JG, Warren PH, Gaston KJ. Urban domestic gardens (IX): Composition and richness of the vascular plant flora, and implications for native biodiversity. Biological Conservation, 2006, 129: 312-322.

[29] Stewart GH, Meurk CD, Ignatieva ME, Buckley HL, Magueur A, Case BS, Hudson M, Parker M. Urban Biotopes of Aotearoa New Zealand (Urbanz) II: Floristics, biodiversity and conservation values of urban residential and public woodlands, Christchurch. Urban Forestry & Urban Greening, 2009, 8: 149-162.

[30] Sun WQ. Quantifying species diversity of streetside trees in our cities. Journal of Arboriculture, 1992, 18: 91-93.

[31] Tcpa. The essential role of green infrastructure: eco-towns green infrastructure worksheet. 2008, London, UK: Town and Country Planning Association

[32] Thaiutsa B. Urban green space, street tree and heritage large tree assessment in Bangkok, Thailand. Urban Forestry & Urban Greening, 2008, 7: 219-229.

[33] Thomas I, Frankhauser P, Biernacki C. The morphology of built-up landscapes in Wallonia (Belgium): A classification using fractal indices. Landscape and Urban Planning, 2008, 84: 99-115.

[34] Twagiramungu F. Environmental profile of Rwanda. 2006, Kigali, Rwanda: European Commission

[35] Wong KMG. Vertical cities as a solution for land scarcity: The tallest public housing development in Singapore. Urban Design International, 2004, 9: 17-30.

[36] Yang LR, Yang XB, Wu QS, Li DH, Luo ZM, Zhang CF. Plant diversity of the artificial ecosystem in Zhayun Township, Qiongzhong, Hainan. Journal of Wuhan Botanical Research, 2010, 28(5): 589-597.

[37] Zhang B, Li WH, Xie GD, Xiao Y. Water conservation of forest ecosystem in Beijing and its value. Ecological Economics, 2008, 69: 1416-1426.