ENVIRONMENTAL QUALITY CHANGES OF SINGKARAK WATER CATCHMENT AREA USING REMOTE SENSING DATA

Lake Singkarak in west Sumatera is currently in very poor condition and become one of the priorities in the government lake rescue program. High sedimentation rate from soil erosion has caused siltation, decreasing of quality and quantity of lake water. Monitoring of the environment quality changes of the lake and its surrounding are required. This study used Landsat and SPOT satellite data in periods of 2000-2011 to evaluate environmental quality parameters of the lake such as land cover, lake water quality (total suspended solid), water run-off, and water discharge in Singkarak lake catchment area. Maximum likelihood classifier was used to obtain land cover. Total suspended solid was extracted using Doxaran algorithm. The look up table and rational method were used to estimate run-off and water discharge. The results showed that the decreasing of forest area and the increasing of settlement were consistent with the increasing of average run-off and water discharge in Paninggahan and Sumpur sub-catchment area. The results were also consistent with the increasing of TSS in Singkarak lake, where TSS increased from around 2-3 mg/l up to 5-6 mg/l in the periods of 2000-2011

DETERMINATION OF FOREST AND NON-FOREST IN SERAM ISLAND MALUKU PROVINCE USING MULTI-YEAR LANDSAT DATA

Seram Island is one of the islands in Maluku Province. Forest in Seram Island still exists because there is Manusela National Park, but they should be monitored. The forest and non-forest information is usually obtained through the classification process from single remote sensing data, but in certain places in Indonesia it is difficult enough to get  single Landsat data with cloud free, so annual mosaic was used. The aim of this research was to analyze the stratification zone, their indices and thresholds to get spatial information of annual forest area in Seram Island using multi-year Landsat Data. The method consists of four stages: 1) analyzing the base probability result for determination of stratification zone 2) determining the annual forest probability by applying indices from stage-I, 3) determining the spatial information of forest and non-forest annual phase-I by searching the lowest boundary of forest probability, and 4) determining the spatial information of forest and non-forest annual phase-II using the method of permutation of three data and multi-year forest rules. The results of this study indicated that Seram Island  could be coumpond into one stratification zone with three indices. The index equations were B2+B3-2B for index-1, B3+B4 for index-2, and -B3+B4 for index-3.   The threshold  of  index 1, 2, and 3 ranged between -60 and 0, 61 and 104, and 45 and 105, respectively. The lowest boundary  of forest probability in Seram Island since 2006 to 2012 have a range between 46% and 60%. The last result was the annual forest spatial information phase II where the missing data on the forest spatial information phase I decreased. The information is very important to analyze forest area change, especially in Seram Island.

GROWTH PROFILE ANALYSIS OF OIL PALM BY USING SPOT 6 THE CASE OF NORTH SUMATRA

Oil Palm (Elaeis guineensis Jack.) is one of the world’s most important tropical tree crops. Its expansion has been reported to cause widespread environment impacts. SPOT 6 data is one of high resolution satellite data that can give information more detail about vegetation and the age of oil palm plantation. The objective of this study was to analyze the growth profile of oil palm and to estimate the productivity age of oil palm. The study area is PTP N 3 in Tebing Tinggi North Sumatera Indonesia.  The method that used is NDVI analysis and regression analysis for getting the model of oil palm growth profile. Data from the field were collected as the secondary data to build that model. The data that collected were age of oil palm and diameters of canopy for every age.   Results indicate that oil palm growth can be explained by variation of NDVI with formula y = -0.0004x2 + 0.0107x + 0.3912, where x is oil palm age and  Y is NDVI of SPOT, with R² = 0.657. This equation can be used to predict the age of oil palm for range 4 to 11 years with R2 around 0.89

APLIKASI MODEL GEOBIOFISIK NDVI UNTUK IDENTIFIKASI HUTAN PADA DATA SATELIT LAPAN-A3

ABSTRAKSatelit LAPAN-A3/IPB merupakan satelit mikro yang dibuat anak bangsa dalam rangka membangun kemandirian bangsa bidang Keantariksaaan. Satelit ini memiliki 4 band diantaranya adalah 3 gelombang tampak dan 1 inframerah dekat. Mengingat  merupakan satelit baru, perlu dilakukan kajian dan penelitian terhadap kemampuan karakteristik sensor untuk mengidentifikasi sumberaya alam, salah satunya hutan. Pada penelitian ini selain menggunakan data satelit LAPAN-A3, juga digunakan data Landsat-8 sebagai data pembanding untuk pengujian tingkat akurasi ketelitian. Penentuan ekstraksi parameter geobiofisik identifikasi hutan menggunakan model Normalized Difference Vegetation Index (NDVI) dengan nilai ambang batas untuk identifikasi hutan.  Hasil penelitian dengan data satelit LAPAN-A3 menujukkan bahwa kisaran ambang batas untuk indentifikasi hutan adalah di atas 0,65 pada  skala indeks vegetasi -1 (minus satu) sampai +1 (plus satu), dengan tangkat akurasi 60% setelah dibandingkan dengan nilai NDVI pada data Landsat-8

Spatial and Temporal Analysis of Land Use Change for 11 years (2004-2014) in Sub-Watershed Sumpur Singkarak

The pressure of population growth and the economy has an impact on changes in land use in Sub-watershed Sumpur Singkarak West Sumatra, Indonesia. Changes in land use are analyzed spatially and temporally using satellite imagery Landsat TM 7 and 8 (resolution 30 m) that has been in the interpretation of 2004 to 2014. The analysis is done by comparing the changes in land use in the area of forest, farming and settlement. From the analysis it can be concluded that there has been a decline in forest area of 128 ha (1.6%), an increase in mixed-farming area of 146 ha (16.1%), an increase in settlement area of 143 ha (26%) for 11 years in Sub-watershed. In 2011, a change of 3125 ha of rice-paddy which have been changed become dry land an area of 2645 ha. This is due to the farming community, prefer to plant horticulture and crop plant from the rice plant.In the protected forest area has been used for settlement area of 1.37 ha and for dry land area of 11.41 ha. In the tourist nature reserve forest areas have been used for rice paddy area of 0:33 ha and for dry land area of 42.91 ha.

Spatial and Temporal Analysis of Land Use Change for 11 years (2004-2014) in Sub-Watershed Sumpur Singkarak

The pressure of population growth and the economy has an impact on changes in land use in Sub-watershed Sumpur Singkarak West Sumatra, Indonesia. Changes in land use are analyzed spatially and temporally using satellite imagery Landsat TM 7 and 8 (resolution 30 m) that has been in the interpretation of 2004 to 2014. The analysis is done by comparing the changes in land use in the area of forest, farming and settlement. From the analysis it can be concluded that there has been a decline in forest area of 128 ha (1.6%), an increase in mixed-farming area of 146 ha (16.1%), an increase in settlement area of 143 ha (26%) for 11 years in Sub-watershed. In 2011, a change of 3125 ha of rice-paddy which have been changed become dry land an area of 2645 ha. This is due to the farming community, prefer to plant horticulture and crop plant from the rice plant.In the protected forest area has been used for settlement area of 1.37 ha and for dry land area of 11.41 ha. In the tourist nature reserve forest areas have been used for rice paddy area of 0:33 ha and for dry land area of 42.91 ha

EVALUASI REHABILITASI LAHAN KRITIS BERDASARKAN TREND NDVI LANDSAT-8 (Studi Kasus: DAS Serayu Hulu)

Pemanfaatan penginderaan jauh dalam memantau vegetasi sudah banyak dilakukan, tetapi pemanfaatannya untuk mengevaluasi rehabilitasi di lahan kritis masih sangat jarang. Kegiatan rehabiliatsi hutan dan lahan dilakukan karena makin meningkatnya lahan kritis. Kegiatan rehabilitasi tersebut perlu dievaluasi, mengingat banyak sekali dana, waktu, dan tenaga yang diperlukan. Selama ini evaluasi dilakukan dengan cara langsung mendatangi lokasi rehabilitasi dengan memantau pertumbuhan tanaman pada setiap akhir tahun sampai akhir tahun ketiga. Menurut ketentuan peraturan yang berlaku, rehabilitasi dapat dikatakan berhasil apabila 90% vegetasi yang ditanam bisa tumbuh di akhir tahun ketiga. Kegiatan evaluasi dengan cara memantau kondisi vegetasi atau kerapatannya dapat dilaksanakan dengan memanfaatkan data penginderaan jauh, karena data tersebut mempunyai sifat multi temporal dan cakupan yang luas dan ketersediannya yang berlimpah dan mudah didapat. Data penginderaan jauh yang digunakan adalah Landsat-8 tahun 2013 sampai dengan 2018 dan metode evaluasi adalah analisis NDVI dari waktu ke waktu menggunakan SIG. Hasilnya adalah bahwa dari hasil survey yang diperoleh di kawasan APL terdapat lokasi rehabilitasi di lahan tidak kritis, agak kritis, kritis, dan sangat kritis dan berturut-turut keberhasilan rehabilitasi untuk APL_TK; APL_K; APL_AK; APL_SK jika NDVI melampaui nilai 0,337; 0,465; 0,493; 0,490 setelah bulan ke 21,8; 24,5; 26, dan 25,8

UJI MODEL FASE PERTUMBUHAN PADI BERBASIS CITRA MODIS MULTIWAKTU DI PULAU LOMBOK (THE TESTING OF PHASE GROWTH RICE MODEL BASED ON MULTITEMPORAL MODIS IN LOMBOK ISLAND)

Model testing is a step that must be done before operational activities. This testing aimed to test rice growth phase models based on MODIS in Lombok using multitemporal LANDSAT imagery and 4eld data. This study was carried out by the method of analysis and evaluation in several stages, these are : evaluation of accuracy by multitemporal Landsat 8 image analysis, then evaluation by using 4eld data, and analysis of growth phase information to calculate model consistency. The accuracy of growth phase model was calculated using Confusion Matrix. The results of stage I analysis for phase of April 30 and July 19 showed the accuracy of the model is 58-59 %, while the evaluation of stage II for phase of period July 19 with survey data indicated that the overall accuracy is 53 %. However, the results of model consistency analysis show that the resulting phase of the smoothed MODIS imagery shows a consistent pattern as well as the EVI pattern of rice plants with an 86% accuracy, but not for pattern data without smoothing. This testing give conclusion is the model is good, but for operational MODIS input data must be smoothed 4rst before index value extraction.ABSTRAKUji model adalah sebuah tahapan yang harus dilakukan sebelum model tersebut digunakan untuk kegiatan yang bersifat operasional. Penelitian ini bertujuan untuk menguji akurasi model fase pertumbuhan padi berbasis MODIS di pulau Lombok terhadap citra Landsat multiwaktu dan data lapangan. Penelitian dilakukan dengan metode analisis dan evaluasi secara bertahap. Pertama, evaluasi akurasi menggunakan analisis citra Landsat 8 multiwaktu. Pada tahap kedua menggunakan data referensi hasil pengamatan lapangan, sedangkan tahap ketiga dilakukan analisis informasi fase pertumbuhan untuk mengetahui tingkat konsistensi model. Akurasi model fase pertumbuhan dihitung menggunakan matrik kesalahan. Hasil analisis dan evaluasi tahap I terhadap informasi fase 30 April dan 19 Juli menunjukkan bahwa ketelitian model mencapai 58-59 %, sementara hasil evaluasi tahap II terhadap fase periode 19 Juli menggunakan data hasil survei 20-25 Juli menunjukkan akurasi keseluruhan 53 %. Namun, hasil analisis konsistensi model menunjukkan bahwa fase yang dihasilkan dari citra MODIS yang di-smoothing menunjukkan pola yang konsisten sebagaimana pola EVI tanaman padi dengan akurasi 86 %, sedangkan pola EVI citra MODIS yang tidak di-smoothing tidak konsisten. Berdasarkan hasil ini disimpulkan bahwa model ini cukup baik, tetapi dalam operasionalnya perlu dilakukan smoothing citra MODIS input terlebih dahulu sebelum ekstrak nilai indek (EVI)