Prita Ayu Permatasari

Leaf Area Index (LAI) in different type of agroforestry systems based on hemispherical photographs in Cidanau Watershed

Ecological functions of agroforestry systems have perceived benefit to people around Cidanau Watershed, especially in the protection of water quality. The main causes of the problems encountered in the Cidanau Watershed are associated with the human factors, especially encroachment and conversion of forest into farmland. The encroachment has made most forest in Cidanau Watershed become bare land. To preserve the ecological function of agroforestry systems in Cidanau Watershed, monitoring of the condition of the vegetation canopy in agroforestry systems is really needed. High intensity thinning of crown density due to deforestation can change stand leaf area index dramatically. By knowing LAI, we can assess the condition of the vegetation canopy in agroforestry systems. LAI in this research was obtained from Hemispherical Photographs analysis using the threshold method in HemiView Canopy Analysis Software. Our research results indicate that there are six types of agroforestry in Cidanau Watershed i.e. Sengon Agroforestry, Clove Agroforestry, Melinjo Agroforestry, Chocolate Agroforestry, Coffee Agroforestry, and Complex Agroforestry. Several factors potentially contribute to variations in the value of LAI in different types of agroforestry. The simple assumptions about differences ranges of LAI values on six types of agroforestry is closely related to leaf area and plant population density.

The effect of land use change on water quality: A case study in Ciliwung Watershed

Ciliwung is the biggest river in Jakarta. It is 119 km long with a catchment area of 476 km2. It flows from Bogor Regency and crosses Bogor City, Depok City, and Jakarta before finally flowing into Java Sea through Jakarta Bay. The water quality in Ciliwung River has degraded. Many factors affect water quality. Understanding the relationship between land use and surface water quality is necessary for effective water management. It has been widely accepted that there is a close relationship between the land use type and water quality. This study aims to analyze the influence of various land use types on the water quality within the Ciliwung Watershed based on the water quality monitoring data and remote sensing data in 2010 and 2014. Water quality parameters exhibited significant variations between the urban-dominated and forest-dominated sites. The proportion of urban land was strongly positively associated with total nitrogen and ammonia nitrogen concentrations. The result can provide scientific reference for the local land use optimization and water pollution control and guidance for the formulation of policies to coordinate the exploitation and protection of the water resource.

Water quality of Cisadane River based on watershed segmentation

The growth of population and industrialization combined with land development along river cause water pollution and environmental deterioration. Cisadane River is one of the river in Indonesia where urbanization, industrialization, and agricultural are extremely main sources of pollution. Cisadane River is an interesting case for investigating the effect of land use to water quality and comparing water quality in every river segment. The main objectives with this study were to examine if there is a correlation between land use and water quality in Cisadane River and there is a difference in water quality between the upstream section of Cisadane River compared with its downstream section. This study compared water quality with land use condition in each segment of river. Land use classification showed that river segment that has more undeveloped area has better water quality compared to river segment with developed area. in general, BOD and COD values have increased from upstream to downstream. However, BOD and COD values do not show a steady increase in each segment Water quality is closely related to the surrounding land use.Therefore, it can not be concluded that the water quality downstream is worse than in the upstream area.

Relationship between land use and water quality in Pesanggrahan River

Pesanggrahan River watershed has several activities such as residential and commercial area in its catchment area. The purpose of this study was to analyse water quality related to spatial land use in Pesanggrahan River using GIS Analysis. River water quality in some locations, did not meet water quality standard of class III. From pollution load estimation it was revealed that segment 2 (Bogor City) has the highest BOD, COD, and TSS of 15,043 kg/day, 25,619 kg/day, and 18,104 kg/day respectively. On the other hand, the most developed area in Pesanggrahan Watershed is located in segment 7 (24.5%). Hence, it can be concluded that although an area has a fairly small developed area, high urban activity can cause high BOD, COD, and TSS.

Monitoring 2015 drought in West Java using Normalized Difference Water Index (NDWI)

Drought is a slow developing phenomenon that accumulates over period and affecting various sectors. It is one of natural hazards that occurs each year, particularly in Indonesia over Australian Monsoon period. During drought event, vegetations cover can be affected by water stress. Normalized Difference Water Index (NDWI) is a method for water resource assessment and known to be strongly related to the plant water content. NDWI is produced from MODIS bands Near-infrared (NIR) and Short Wave Infrared (SWIR). This research aims to monitor drought using NDWI in West Java during El Nino 2015 and its impact on rainfall variability. The result showed rainfall was decreased significantly starting from May-June, then increased in November. According to NDWI, it also showed that mostly West Java Region affected by drought during May-November. Very strong drought occurred on September-November. On December, areal extent of drought was decreasing significantly because rainfall had increased during November. Generally, areal extent of drought in West Java was dominated by strong and moderate drought. It implied that El Nino 2015, give great impact on increasing drought and decreasing rainfall in West Java. NDWI can be detected drought occurrence as it have good correlation with rainfall spatially.

Monitoring tropical peatland ecosystem in regional scale using multi-temporal MODIS data: Present possibilities and future challenges

Many studies on peatland ecosystem have been focused on forest conversion or forest degradation as a single pathway, meanwhile; in the context of peatland ecosystem, the change in land surface is more complicated since it can be categorized into two types and mechanisms: 1) gradual change, caused by interannual climate variability and forestland degradation, and 2) abrupt change, caused by disturbances such as deforestation and wildfires. Understanding this change types is needed for conservation and management, particularly to improve understanding of terrestrial environmental change in peatland ecosystem. In such situation, simultaneous analysis of land surface attributes from long-term datasets and seasonal variation seems to be a way to monitor the tropical peatland ecosystem. This analysis provides information about how the changes occurred accurately as well as how big are these affected areas. In this article, the feasibility of using long-term MODIS data for monitoring the dynamics change in peatland ecosystem is examined. The temporal vegetation dynamics of long-term MODIS datasets offer great promise for characterizing gradual change as well as abrupt change at large scale, however, the mixed pixel issue and some residual noises in temporal sequences are quite problematic when using MODIS data.

Mangrove mapping and change detection in Sungai Asam Village, Indragiri Hilir Regency, Riau Province

Indonesia is an archipelago in the tropical climate that has the largest mangrove forest in the world. Based on data from the Ministry of Environment and Forestry, mangrove forest area is estimated about 9 million hectares in 2000. However, this amount is reduced drastically. Approximately, sixty percent of mangrove forest area in 2006, has been lost, damaged, and changed into ponds, plantation, agriculture area, and settlement. Indragiri Hilir is one of regency in Riau Province which has the high potential diversity of mangrove. Based on interpretation of Landsat 8 satellite imagery in June - July 2013, mangrove forest in Indragiri Hilir reached 100,211.23 hectares. The area of mangrove forest is estimated to decrease, due to land use and land cover change. Based on land cover change map, mangrove forest area in Sungai Asam Village has increased in 20 years.