analysis techniques have made a notable progress in these studies (Ierodiaconou
et al. 2005).
Therefore, a case study of Bentong River basin in Pahang state, Malaysia has
been analyzed to illustrate the effects and significance of spatial land uses and
landscape patterns on water quality. Normally, it is somewhat difficult to assert
and clarify these relationships in rivers, due to the continuous inputs from upstream.
Nevertheless, this study utilized the basic concept that surface settings and spatial
composition will categorically change water quality in adjacent water systems.
Bentong River is constituted of multiple tributaries with Kelau River, Semantan
River, Benus River, and Telemung River representing the major ones. Bentong
catchment is located in the western part of Pahang State, Malaysia with an estimated
area of 3401 km
2 . The average annual total rainfall received in Bentong catchment
area is approximately 1855 mm, the mean rainfall distribution throughout the year,
according to the previous rainfall records of the past 35 years (Malaysian Meteorological Department 2019). The river basin contains various agricultural and industrial areas with a vast dispersion of forests. Wastewaters are discharged into the
middle and lower reaches of the river. Large-scale development projects in the entire
state, including Bentong, have resulted in the clearing of hundreds of square miles of
land for oil palm and rubber plantations, and the resettling of several hundred
thousand people in new villages under the federal agencies and institutions like the
Federal Land Development Authority (FELDA), Federal Land Consolidation and
Rehabilitation Authority (FELCRA), and Rubber Industry Smallholders Development Authority (RISDA) has also affected the quality of river basin.
With the help of Fig. 2.1, a Digital elevation model (12.5 resolution) data and
maps interpreted from 2011 ASFs (Vertex) images used to delineate and extract the
stream network within the Bentong watershed and land use and cover composition
map are observed by using ArcGIS 10.2 techniques (Shehab et al. 2020). Depending
upon the types of land uses, seven different zones are categorized and further
reclassified into four major categories based upon their significance level. These
major categories are: (1) forests; (2) agricultural land; (3) residential areas; and
(4) facilities and industrial areas (Fig. 2.1B). Shehab et al. (2020) have divided the
study area into seven zones to better understand and quantify the impacts of certain
land types or landscape patterns on water quality and to compare their relationships
with water characteristics. Composition percentage of land use types for seven
different zones is illustrated in (Fig. 2.2. The classification is largely based on stream
network and sampling sites.
Furthermore, several landscape metrics are selected to determine the impact of
landscape structure on water quality. FRAGSTATS 4.1 software, which is a spatial
pattern analysis program for quantifying the structure of landscapes, is used to
calculate these metrics using the land use data in the study area. The applied metrics
are patch density (PD), edge density (ED), Shannon’s diversity index (SHDI),
Contagion (CONTAG), largest patch index (LPI), cohesion index (COHE), shape
index (SHMN), aggregation index (AI), and mean Euclidean nearest neighbor index
(ENNMN). These metrics have been established based on landscape, class, and
patch scale, all of which differ in definition and measurement. Here, the indices will
2 Landscape Perspective to River Pollution: A Case Study of Bentong River,. . .
23
et al. 2005).
Therefore, a case study of Bentong River basin in Pahang state, Malaysia has
been analyzed to illustrate the effects and significance of spatial land uses and
landscape patterns on water quality. Normally, it is somewhat difficult to assert
and clarify these relationships in rivers, due to the continuous inputs from upstream.
Nevertheless, this study utilized the basic concept that surface settings and spatial
composition will categorically change water quality in adjacent water systems.
Bentong River is constituted of multiple tributaries with Kelau River, Semantan
River, Benus River, and Telemung River representing the major ones. Bentong
catchment is located in the western part of Pahang State, Malaysia with an estimated
area of 3401 km
2 . The average annual total rainfall received in Bentong catchment
area is approximately 1855 mm, the mean rainfall distribution throughout the year,
according to the previous rainfall records of the past 35 years (Malaysian Meteorological Department 2019). The river basin contains various agricultural and industrial areas with a vast dispersion of forests. Wastewaters are discharged into the
middle and lower reaches of the river. Large-scale development projects in the entire
state, including Bentong, have resulted in the clearing of hundreds of square miles of
land for oil palm and rubber plantations, and the resettling of several hundred
thousand people in new villages under the federal agencies and institutions like the
Federal Land Development Authority (FELDA), Federal Land Consolidation and
Rehabilitation Authority (FELCRA), and Rubber Industry Smallholders Development Authority (RISDA) has also affected the quality of river basin.
With the help of Fig. 2.1, a Digital elevation model (12.5 resolution) data and
maps interpreted from 2011 ASFs (Vertex) images used to delineate and extract the
stream network within the Bentong watershed and land use and cover composition
map are observed by using ArcGIS 10.2 techniques (Shehab et al. 2020). Depending
upon the types of land uses, seven different zones are categorized and further
reclassified into four major categories based upon their significance level. These
major categories are: (1) forests; (2) agricultural land; (3) residential areas; and
(4) facilities and industrial areas (Fig. 2.1B). Shehab et al. (2020) have divided the
study area into seven zones to better understand and quantify the impacts of certain
land types or landscape patterns on water quality and to compare their relationships
with water characteristics. Composition percentage of land use types for seven
different zones is illustrated in (Fig. 2.2. The classification is largely based on stream
network and sampling sites.
Furthermore, several landscape metrics are selected to determine the impact of
landscape structure on water quality. FRAGSTATS 4.1 software, which is a spatial
pattern analysis program for quantifying the structure of landscapes, is used to
calculate these metrics using the land use data in the study area. The applied metrics
are patch density (PD), edge density (ED), Shannon’s diversity index (SHDI),
Contagion (CONTAG), largest patch index (LPI), cohesion index (COHE), shape
index (SHMN), aggregation index (AI), and mean Euclidean nearest neighbor index
(ENNMN). These metrics have been established based on landscape, class, and
patch scale, all of which differ in definition and measurement. Here, the indices will
2 Landscape Perspective to River Pollution: A Case Study of Bentong River,. . .
23