This paper analyzed and mapped the impact of built environment (BE) on socio-ecological services along Dar es Salaam metropolitan coastline. In the period of 1995-2016, burgeoning population exacerbated high rate of construction processes and activities. Such anthropic initiatives affect the benefits and values delivered by landscape wetlands, estuaries, beach areas, open space and greenery patches in Dar es Salaam coastline. Motivated to understanding socio-ecological impacts (SEIs) of BE along the coastline; the study applied focus group discussions (FGDs) method to identify SEIs, and their category as either positive or negative. Using analytical hierarchy process (AHP) generated weight to each SEIs; thereafter combined that weight with landuse landcover (LULC) change statistics of each of the 67 wards involved in the study. Mapping results of geographically weighted regression and inverse distance weighting (IDW) interpolation (ArcMap v10.3) displayed the variables relationship magnitudes and distribution in positive and negative SEIs for year 1995, 2005 and 2016. logical and social systems [4]. Such intertwining feedbacks results in complex systemic relationship, termed as socio-ecological system (SES) [5] [6] [7].Existence of human desire for improved economic and social services in SES are external stimuli to coastline resources utilization hence degradation of ecological system [5]. Studies [8] explain that coastline, also referred to as coastal zone, ranges from 60 to 200 kilometre inland and 50 m depth of ocean water system. In between exists highly fertile areas like continental shelf, estuaries and wetlands at both low and high tide periods [9]; these fertile characters are a reason for dominant human perturbation in such areas [10] [11]. While [12] justified the relationship of anthropogenic activities and coastal zone, little has done to disclose the existing link of BE and its impact on SES.BE as a product of construction activities [13], in the search for suitable and comfortable places for recreation, residence and work; impacts the landscape by aggravating vegetation cover clearance, waste generation and permanent consumption of a piece of land [14] [15]. The habitat loss and fragmentation caused by such impacts account significantly for biodiversity loss. According to [16], the functioning of biodiversity species are greatly the determinant of the quality and quantity of services derived from SES. Thus, state of landscape loss or gain of such biological component is a socio-ecological impact (SEI) that alters SES functioning capacity [17]. Scholars such as [18] and [19] typify that some of the positive SEIs include cooling, shadow, air filtration, climate variability and flood prevention by trees; pollinations by avian and arthropods species as well as medicines and food from both fauna and flora.However, irreversible anthropic construction activities provoke landscape environmental challenges as result of megacities development processes and activities [20] [21]. In the search for quality prod...

The degradation of any ecosystem services (ES) and the benefits human being enjoy from nature freely involve multifaceted processes such as those in built environment. The ecological security and multiple functions of the coastal zone of Dar es Salaam is of paramount importance to the sustainability of its natural and anthropogenic systems. Therefore, permanent/temporary conversion of a piece of land for construction space provisions profoundly affects the functionality and connectedness of nature–anthropogenic ecosystem. This study quantified land use landcover changes from Landsat satellite imageries, then evaluated the changes using recognizable coefficients for ecosystem services values (ESV). Applying Geographical Information System (GIS) techniques, the impacts of built environment on ESV were analysed using land use landcover change (LULCC) transfer matrix, carbon stock dynamics and soil erosion influence on soil fauna. The results revealed expansive BE from 10.6 percent in 1995 to 22.8 percent in 2016. Loss of forest by 64.5 percent in the study period explained the declining total ESV by 56.1 percent and per capita recreation potential by 2.3 percent. Similarly, decreasing forest cover led to high carbon dioxide emission, notably, the 353.24 t CO2 ha-1 yr-1 in the period between 1995 and 2005. Furthermore, in 1995 bushland experienced high soil erosion while in 2016 built environment displayed a similar trend as the rest of the land use landcover (LULC) classes. From geospatial analysis, the southern area displayed significant vegetation cover change as compared to the built environment dominant in the northern section of Dar es Salaam coastline. Initiative to reducing built environment by 1 percent saves forest loss by 5.28 percent and carbon sequestration at a tune of 28.95 t CO2 ha-1 yr-1; hence improves ecological services values by 4.60 percent.