Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah <p>Buletin Tanah dan Lahan merupakan media yang menyajikan artikel mengenai hasil penelitian dan telaah perkembangan mutakhir dalam bidang ilmu tanah, lahan, dan ilmu wilayah sebagai bahan kajian utama. Buletin Tanah dan Lahan diterbitkan tiga kali setahun yaitu pada bulan Januari, Mei dan September oleh Departemen Ilmu Tanah dan Sumberdaya Lahan.</p> en-US <span style="color: #000000; font-family: Verdana, Arial, Helvetica, sans-serif; font-size: 10px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: #ffffff; text-decoration-style: initial; text-decoration-color: initial; display: inline !important; float: none;">Departemen Ilmu Tanah dan Sumberdaya Lahan, Faperta IPB</span> b.tanahlahan_soilipb@yahoo.com (Asdar Iswati) desi_nadalia@yahoo.com (Desi Nadalia) Fri, 18 Aug 2017 15:59:32 +0700 OJS 3.1.2.4 http://blogs.law.harvard.edu/tech/rss 60 PENGARUH PEMANGKASAN DAN PEMUPUKAN TERHADAP DINAMIKA RHIZOSFER TANAMAN KILEMO (Litsea cubeba) https://journal.ipb.ac.id/index.php/btanah/article/view/17684 <p>Kilemo (Litsea cubeba L. Persoon) is the one of plant which cultivated as a medicine plant, such an essential oil. This plant harvested at the tip of leaves and the leaves, therefore the management include pruning and fertilizing. This research was aimed to observe the effect of pruning and fertilizing toward population of rhizosphere communities on kilemo (Litsea cubeba L. Persoon). Pruning was practiced on to kilemo after 2 years and four fertilizing treatments i.e control (without fertilizing), NPK fertilizer, microfertilizer and compost,were applied on to the plant with pruning and without pruning. Results of this research showed that pruning was able to decrease population of Azotobacter, P solubilizing microorganism (MoPP), cellulose solubilizing microorganism (MPS). Pruning with fertilizing NPK treatment also decreased population of microorganism. Furthermore, giving organic fertilizer was able to increase population of Azotobacter microorganism and P solubilizing microorganism (MoPP). Meanwhile, microfertilizer only increased population of cellulose solubilizing microorganism (MPS).</p><p><br />Keywords: Fertilizing, kilemo, microorganism, pruning, rhizosphere</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17684 Fri, 18 Aug 2017 15:59:32 +0700 STUDI GEOMORFOLOGI KABUPATEN KEDIRI DAN PEMETAAN BAHAYA DAN RESIKO ALIRAN LAHAR GUNUNGAPI KELUD https://journal.ipb.ac.id/index.php/btanah/article/view/17685 <p>Kelud volcano is an active volcano in Java, located close to Kediri District. The volcano frequently produce lahar flow contributing to shape its geomorphology characteristics, and some time endanger to people at the area. This research aims are 1) mapping of landform and landuse, and 2) mapping of lahar hazard and risk of Gunung Kelud at Kediri District. The methods implemented are: 1) morphometric analysis and spatial analysis using GIS. Hazard area is divided into proximal area (volcanic cone area) and medial-distal area (slope area), 2) field observation and discussion for mapping of lahar expose area, and 3) identifying risk area through overlay of hazard and landuse map. The results show that fluvio-vulcanic areas is the largest area (60,50%) at Kediri District/City. The dominant landuse is irrigated paddy area (41,1%) at the fluvio-vulcanic landform, and the very hazardous areas is located at the proximal area and the highest risk area of lahar is located at Plosoklaten Subdistrict (46 ha).</p><p><br />Keywords: Geomorphology, hazard, Kelud Volcano, lahar, risk</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17685 Sun, 01 Jan 2017 00:00:00 +0700 PENGARUH Trichoderma Sp. DAN MOLASE TERHADAP SIFAT BIOLOGI TANAH DI SEKITAR LUBANG RESAPAN BIOPORI PADA LATOSOL DARMAGA https://journal.ipb.ac.id/index.php/btanah/article/view/17686 <p>Organic waste addition into the biopore infiltration hole could improve soil biological. The decomposition organic waste in the biopore infiltration hole could be accelerated by adding activator Trichoderma sp. and molasses. This research aimed at finding out the effect of giving Trichoderma sp. and molasses in soil biological properties including population and diversity of soil fauna, microbes and fungi population at arround the biopore infiltration hole. Design model that used was randomized block design (RBD) with Least Significant Difference (LSD) test on the level of trust 5%. The treatment of this research were, P0: without organic waste (SO) + molasses (M) + Trichoderma sp. (T), P1: addition of SO, P2: addition of SO + M, P3: addition of SO + T, and P4: addition of SO + M + T. The result of this research showed that the addition of Trichoderma sp. (SO+T) and molasses (SO + M) in biopore infiltration hole could improve the soil biological properties. It was indicated by the high of soil microbes population 1,59 x 106 CFU (Colony Forming Unit)/g ADW (Absolute Dry Weight) and significantly higher compared to the P0. Both of the treatments also had the highest population of soil fauna than other treatments, that were 6071 individual m-2 (SO + T) and 1908 individual m-2 (SO + M), and had high population of soil fungi, that were 1,26 x 104 CFU g-1 ADW soil (SO + T) and 1,42 x 104 CFU g-1 ADW soil (SO + M), nevertheless they all did not have significantly effect in increasing the diversity of soil fauna.</p><p><br />Keywords: Biopore Infiltration Hole, molasses, soil biological properties, Trichoderma sp.</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17686 Sun, 01 Jan 2017 00:00:00 +0700 PEMANFAATAN WATER ABSORBENT UNTUK MENINGKATKAN RETENSI AIR DAN PERTUMBUHAN TANAMAN JAGUNG (Zea mays L.) https://journal.ipb.ac.id/index.php/btanah/article/view/17687 <p>Water availability is one of principal problem in the system of dry-land farming, especially for food crops. Every plants needs constant water supply to grow, but this is not obtained in dry land farming that rely mainly on rain as a water resource. The lack of water availability in dry season caused decreasing of plant’s growth and productivity. In order to increase water availability, this research is using super water absorbent (SWA) from cassava’s starch to hold water and release it slowly. The purposes of this research are analyzing the impact of cassava’s starch SWA to the volume of water that is retained by soil and growth of corn (Zea mays L). The result showed that application of water absorbent tend to increase the ammont of water retained by soil, eventhough the effect was not significant. Application of water absorbent result in significanly better corn growth as compared to control (no water absorbent). Nevertheless the application of water absorbent fail to maintain crop growth at optimum level. The treatment that retained most water is cassava starch SWA with 0.2 g/kg the dosages of spread mix in soil make every 14 days watering. While, application of cassava’s starch with 0.1 g/kg the dosages of concentrate in soil make every 14 days watering has a significant with the high and leaves’s wide, but not with the number it.</p><p><br />Keywords: Sandy clay, Super Water Absorbant, the volume of water retained by soil, the growth of corn</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17687 Sun, 01 Jan 2017 00:00:00 +0700 PEMODELAN PERUBAHAN PENUTUPAN/PENGGUNAAN LAHAN DENGAN PENDEKATAN ARTIFICIAL NEURAL NETWORK DAN LOGISTIC REGRESSION (STUDI KASUS: DAS CITARUM, JAWA BARAT) https://journal.ipb.ac.id/index.php/btanah/article/view/17688 <p>Land use / cover change may occur due to factors of socio, politic, economy, culture, nature and technology. Geographical Information System can be used to analysis of landuse and connecting to driving factors. This research objectives are : to map land use/cover change in Citarum Watershed between 2000 and 2010, and to model its changing using Artificial Neural Network (ANN) and Logistic Regression (Logit). Land use/cover is interpreted using Landsat of 2010 and 2010, while the model is developed using software Idrisi Selva. Factors used as driving factors used are distance to road, distance to river, district income, slope steepness and population density. The results show that the largest decreased area is sawah (31.873 ha) and rural areas is the largest increasing area (41.574 ha), Sawah areas have been converted to to agricultural area and rural area 24.863 ha and 24.106 ha respectively. Data validation shows that land of 2012 has produce good result where Kappa value is 0,9622 for ANN and value of 0,9642 for Logit. In this case, land use projection using ANN and Logit may predict area of land use change.</p><p><br />Keywords: Artificial Neural Network, land use / cover, Logistic Regression, model</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17688 Sun, 01 Jan 2017 00:00:00 +0700 PENGARUH TRASS DAN KOMBINASI TRASS DENGAN ABU MERAPI TERHADAP SIFAT KIMIA TANAH SERTA PERTUMBUHAN DAN PRODUKSI BIOMASSA TANAMAN PADI (Oryza sativa) PADA TANAH GAMBUT DARI KUMPEH, JAMBI https://journal.ipb.ac.id/index.php/btanah/article/view/17689 <p>The increasing of population annually, needs to increase food availability. On the other hand, the productive land for agriculture have limitations because the large land conversion to non-agricultural land. The use of marginal land such as peat is an attempt to overcome the limited productive land for growing rice. Peat soils have low soil fertility level and acid soil reaction in nature. The conditions of peat soils require amelioration to improve soil fertility. The ameliorants that have potential to increase soil fertility are trass and volcanic ash. The purpose of this research was to examine the effects of trass and its combination with volcanic ash on soil chemical properties and rice growth. The research was conducted in a pot experiment using peat soils from Kumpeh, Jambi. Doses of trass as a single factor treatment were 0, 3, 6, and 9% or 0, 90, 180, and 270 gram/pot, and doses of the combination treatments between trass and volcanic ash were 0+7.5, 1.875+5.625, 3.75+3.75, 5.625+1.875, and 7.5+0% or 0+225, 56.25+168.75, 112.5+112.5, 168.75+56.25, and 225+0 grams/pot, the all treatments compared to standard fertilization. The research design was used Completely Randomized Design (CRD). The results showed that giving the trass as a single factor significantly increased the soil pH, Exchangable Al and Mg, available Zn and Mn, plant height, productive tillers, plant biomass, uptake of K, Si, and plant Zn. The combination trass with volcanic ash significantly increased the soil pH, Exchangable Al, total-N, Exchangable Na, available Zn and Mn, plant height, productive tillers, plant biomass, uptake of P, K, Si, and plant Zn. Beside that, combination trass with volcanic ash significantly improved the efficiency of P and K fertilization.</p><p><br />Keywords: Peat, rice, trass, volcanic ash</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17689 Sun, 01 Jan 2017 00:00:00 +0700 KARAKTERISTIK SIFAT FISIK TANAH PADA SISTEM PENGOLAHAN TANAH KONSERVASI (STUDI KASUS: KEBUN PERCOBAAN CIKABAYAN) https://journal.ipb.ac.id/index.php/btanah/article/view/17690 <p>Intensive soil tillage system in long period time cause detremental of soil physical, chemical, and biological quality. It needs, therefore, oil tillage system that maintaining land well productivity. It is conservation soil tillage system. The research aims to study and compare soil physical properties of conservation tillage and 15 years intensive tillage. Observed parameters were soil texture, organic matter, agregate stability, available water, soil moiture movement, soil macrofauna, and soil macro poroity. The research result shows that soil organic matter, agregate stability, available water, soil moiture movement, soil macrofauna, and soil macro poroity under conservation tillage were higher than 15 years intensive tillage.</p><p><br />Keywords: Conservation soil tillage, soil mositure, soil physical properties</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17690 Sun, 01 Jan 2017 00:00:00 +0700 STUDI GEOMORFOLOGI DAN ANALISIS BAHAYA LONGSOR DI KABUPATEN AGAM, SUMATERA BARAT https://journal.ipb.ac.id/index.php/btanah/article/view/17691 <p>Sumatra island is located at conjunction point of Indo-Australia Plate and Eurasia Plate which move continuesly throughout year. This movement provokes many natural disasters and one is landslide. This research aims: 1) to learn geophology condition of Agam District, and 2) to map landslie vulnerable and hazard area at Agam District. The methods used are (1) using SRTM to understand and map of geomorphology area, and (2) multicritera evaluation using weight and score system. The research results show that geomorphology of Agam Districr is very complex. The western area is coastal plain area, the eastern are is hilly and mountanoues area, at its located at Bukit Barisan Mountain Rigdes. The vulnerability data show that 54,3% areas belong to no vulnerabity status, 14,9% low vulnerability, 12,2% medium vulnerability, and 18,6% high vulnerability. Landslide hazard data shows that 51,3% belongs to no hazard, 14,9% low hazard, 20,2% medium hazard, and 13,6% high hazard. Category of medium and high of landslide hazard and risk distribute ar mountainous area which hase slope between 15% - &gt; 40%.</p><p><br />Keywords: Agam District, geomorphology, GIS, hazard, landslide, vulnerability</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17691 Sun, 01 Jan 2017 00:00:00 +0700 ISOLASI DAN IDENTIFIKASI MIKROBA TANAH PENDEGRADASI SELULOSA DAN PEKTIN DARI RHIZOSFER Aquilaria malaccensis https://journal.ipb.ac.id/index.php/btanah/article/view/17692 <p>Gaharu (agarwood) is one of non-timber forest product. It can be found commonly from trees of genus Aquilaria. Gaharu has been used in religious rituals, as perfume, incense, fragrance, even for medicines. Agarwood formation is caused by microbial infection inside plant tissue host. This research aims to explore soil microbes in rhizosphere of Aquilaria malaccensis which have ability to degrade cellulose and pectin. Screening was conducted to observe cellulase and pectinase activities. In this research, 26 isolates of fungi and 29 isolates of bacteria were isolated. It was found that seven isolates of fungi and six isolates of bacteria showed positive result with clear zone around the cultures. The results of identification showed soil microbes with the highest cellulose and pectin solubilizing index are Bacillus brevis for bacteria and genus Helicoma for fungi.</p><p><br />Keywords: Agarwood, Aquilaria malaccensis, soil microbes</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17692 Sun, 01 Jan 2017 00:00:00 +0700 PENGARUH BAHAN ORGANIK TERHADAP KETERSEDIAAN FOSFOR PADA TANAH-TANAH KAYA Al DAN Fe https://journal.ipb.ac.id/index.php/btanah/article/view/17693 <p>The availability of P that can be absorbed by plants in the soil is generally very low, because P in the soil are manily in adsorbed form. Addition of organic matter can improve the availability of P in the soil, because organic acids that are resulted by decomposition of organic matter have an ability to make chelation of Al and Fe so P may become available. The aim of this research was to study effect of organic matter in releasing and preventing adsorption of P and to study wether the effect of organic matter is better if it is applied before or after P fertilization. This research consisted of five treatments: (1) Soil + straw compost + P fertilizer 2 weeks later, (2) Soil + P fertilizer + straw compost after 2 weeks, (3) Soil + cow manure compost + P fertilizer after 2 weeks, (4) Soil + P fertilizer + cow manure compost after 2 weeks, and (5 ) Soil + P fertilizer. The kind of soil were used in this research Andosol, Latosol, Podsolic. Each treatment on the three soils was incubated for 1 and 2 months. The results showed that treatment of organic matter and P fertilizer addition is increasing pH and P-availability, as well as lowering the Al-dd and Fe-availability on the three soils. Cow manure compost gives a higher effect than straw compost. The addition of organic matter after P fertilization to improve releasing adsorbtion of P and preventing adsorption of P on Latosol and Podsolic. The addition of cow manure compost on Andosol increasing P-availability is better if it is done before P fertilization, meanwhile organic matter addition after P fertilization.</p><p><br />Keywords: Availability of P, compost, organic matter, P Sorption</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17693 Sun, 01 Jan 2017 00:00:00 +0700 KARAKTERISASI FISIK DAN KELEMBABAN TANAH PADA BERBAGAI UMUR REKLAMASI LAHAN BEKAS TAMBANG https://journal.ipb.ac.id/index.php/btanah/article/view/17694 <p>In Indonesia mining activities generally have been applying open mining method that affecting land degradation i.e. deterioration of soil phyical, chemical, and biological quality. According to Act No. 4 year 2009, reclamation of post mining activities is a mandatory to the mining company. One of the reclamation is revegetation. The research aims to study the effect of land revegetation on soil physical and biological as well as soil mositure characteristics on several period of reclamation of post mining activity. The research had been conduced on post mining activity of 2 years (2010 reclamation), 4 years (2008 reclamation), and forest, respectively. Soil moisture characteristics had been measured on several rainfall events. The results shows that soil bulk density, porosity, permability, organic matter, pH had been improved in line with incremental period of the reclamation. Soil mositure content had decreased starting first day untill a week after no rainfall, but it is more than wilting point.</p><p><br />Keywords: Rainfall, reclamation, soil moiture content, soil physical properties</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17694 Sun, 01 Jan 2017 00:00:00 +0700 ANALISIS PERUBAHAN PENGGUNAAN LAHAN DAN ARAHAN PENGGUNAAN LAHAN WILAYAH DI KABUPATEN BANDUNG https://journal.ipb.ac.id/index.php/btanah/article/view/17695 <p>The increasing quality and quantity of life standard is caused by increasing competition on using agricultural and non agricultural land. Objectives of this research are to observe the pattern of land use change in Bandung Regency 2002- 2012, to identify unconformity of current land use to its allocation, to understand regional development hierarchy, to determine factors affecting land use change and to formulate regional land use recommendation. Methods analysis were done spatial analysis for land use change, unconformity identification, skalogram and multiple regression. Predominant land use change are from forest to built-up area, from plantation to built-up area, from paddy field to built-up area, from paddy field to dryland agriculture and from dryland agriculture to built-up area. Existing land use on 2012 showed unconformity with its allocation about 54 ha. Regional hierarchy was not distributed evenly. Subdistricts of east region have higher hierarchy than those of west region. Significant factors affecting land use change from agricultural land to built-up areas are agricultural allocation, development of economic facilities, development of GDRP (gross domestic regional product), acreage of land at slope &lt; 5% and acreage of unfertile soil.</p><p><br />Keywords: Development area, land use, spatial planning</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17695 Sun, 01 Jan 2017 00:00:00 +0700 FLUKS CO2 DARI ANDISOL PADA PENGGUNAAN LAHAN KEBUN TEH DAN TANAH BERA DI DESA TUGU UTARA KECAMATAN CISARUA KABUPATEN BOGOR https://journal.ipb.ac.id/index.php/btanah/article/view/17696 <p>Global warming is due to the increasing of greenhouse gases (GHG) concentration in the atmosphere. There are a lot of informations on CO2 fluxes from peat land, but those from soil mineral is very limited. The purposes of this study are to measure and compare CO2 flux of Andosol used for tea plantation and bare land, and to compare CO2 flux from mineral soils and peat soils. The method used for gas sampling is the closed chamber method and Infra- Red Gas Analyzer (IRGA) was used to measured CO2 concentration. The results showed that CO2 flux in the land used two lands on Andosol is about of 1,00 to 8,00 g C-CO2 m-2 day-1. Daily mean of CO2 fluxes were obtained from 25 weeks are 2,01 g C-CO2 m-2 day-1 (bare land) and 2,81 g C-CO2 m-2 day-1 (tea plantation). Mean daily CO2 flux of tea plantation was a higher than that of CO2 flux from bare land. These results are resembled by the data of microbial populations in the soil of tea plantation that was higher than that of the bare land. That facts indicate that the amount of CO2 flux are more originated from respiration activity that depend on the plant condition and the microbe activity. Andosol’s, Latosol’s and Peat soil’s CO2 fluxes in bare condition are almost the same. It shows that the CO2 flux from soil is not directly proportional to the content of soil organic matter.</p><p><br />Keywords: Andosol, CO2 flux, greenhouse gas, tea plantation, mineral soil</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17696 Sun, 01 Jan 2017 00:00:00 +0700 PENGARUH SWA (SUPER WATER ABSORBENT) PATI SINGKONG TERHADAP SIFAT RETENSI AIR TANAH https://journal.ipb.ac.id/index.php/btanah/article/view/17697 <p>The development of dry-land agriculture often face some constraints, especially when it is related to water needs which is depending on rainwater. Global climate change, that occurs lately has made rainfall patterns become more erratic and less predictable. Therefore, new technology that could help maintaining soil water content is needed to ensure that water availability for plant growth is still sufficient. SWA (Super Water Absorbent) cassava starch is one of a technology that can be used for this purpose. This study was aimed to assess the effect of SWA cassava starch and its comparison to the other water absorbent, for maintaining soil water retention on two different soil textures (clay and sandy clay). The results showed that addition of SWA cassava starch was not significantly different from the other soil water absorbent for maintaining soil water retention. SWA cassava starch performance at clay textured soil was better than sandy clay-textured soil.</p><p><br />Keywords: Soil Water Content, SWA cassava starch.</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17697 Sun, 01 Jan 2017 00:00:00 +0700 PEMANFAATAN JERAMI SEBAGAI PUPUK ORGANIK UNTUK MENINGKATKAN PERTUMBUHAN DAN PRODUKSI PADI (Oryza sativa) https://journal.ipb.ac.id/index.php/btanah/article/view/17698 <p>The leveling off of rice production in Indonesia is caused by degradation of wetlands, which could be characterized by low organic matter content. The factors that cause this issue such as the utilization inorganic fertilizer only, the habit of farmers carrying out rice straw off from wetland or burning of rice straw. The objectives of this research were (1) to test the ability of decomposers in speeded up the decomposition process of rice straw,( 2) examined the effect of organic fertilizer on the growth and yield of rice. The experiment design is completely randomized block. The treatment of decomposers are control (D0), decomposers collection of Prof Iswandi Anas (D1), and commercial decomposers (D2). The treatments in field are NPK 100%, NPK 50%, NPK 50% + PO1, and NPK 50% + PO2 + PB. PO1 and PO2 was an organic fertilizer that each decomposed by D1 and D2, PB was a bioorganic fertilizer. Application of decomposers in this experiment did not speed up the decomposition of rice straw. It is caused because C/N the rice straw low. Application of 50% NPK with organik fertilizer to 100% NPK was not significantly, so that the role of organic fertilizer could not be evaluated. However, there was a tendency of enhancing growth and yield of rice in addition of decomposed organic fertilizer by decomposers.</p><p><br />Keywords: Decomposers, rice production, straw organic fertilizer</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17698 Sun, 01 Jan 2017 00:00:00 +0700 PENGUKURAN RETENSI AIR TANAH GAMBUT MENGGUNAKAN KOMBINASI THREE PHASE METER DAN CERAMIC PLATE https://journal.ipb.ac.id/index.php/btanah/article/view/17699 <p>Water retention and particle density (PD) measurement on tropical peat are rarely. Appropriate measurement method for both are obviously required because these values are very important in peatlands management. This study was aimed to measure water retention of peat soil, to understand the water retention, to draw the pF curves and also to study the effect of changes in soil moisture content on peat volume. Peat soil samples were taken from three locations with different reclamation age. Peat water retention were measured using Ceramic Plate, peat volume were measured using Three Phase Meter, and pF curve equation was made using Genucthen (1980) model. The results showed that the pattern of soil water retention in peat at three locations with different land uses were similar. Water in peat soil was easily lost at low pressure ( pF 0-2 ) and strongly bound by peat soil material at a higher pressure (pF 2-4,2 ). Peat pore was dominated by fine pore ( ± 40 % v/v ) and very fast drainage pore ( ± 30 % v/v ). Interval of available water was very small ( &lt; 10 % v/v ). The changes of water content would affect the volume of peat. Peat soils swell and shrink significantly. The intensity of the swell and sringkage are estimated to depend on the origin and degree of decomposition of peat materials. Particle density of peats were found to vary, so direct measurement must be performed.</p><p><br />Keywords: Genucthen, peat, pF curves, water retention</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17699 Sun, 01 Jan 2017 00:00:00 +0700 FLUKS CO2 DARI TANAH ANDOSOL PADA PENGGUNAAN LAHAN KEBUN SAYUR DAN HUTAN DI KECAMATAN CISARUA KABUPATEN BOGOR https://journal.ipb.ac.id/index.php/btanah/article/view/17700 <p>Agricultural activities are considered as one source of greenhouse gas emissions (GHG). Researchs on GHG emission from agricultural land are mostly done on peat soils, while researchs on mineral soil are still limited. This research was aimed to find out and to compare CO2 flux from vegetable garden, forest, and bare land on Andosol, and to compare CO2 flux from peat soils with these of mineral soils. This research was carried out at tea plantation area of PT Sumber Sari Bumi Pakuan, Tugu Utara Village, Cisarua District, Bogor Regency (Puncak area). Gas samples were taken using a chamber method and CO2 measurement was done using a CO2 Analyzer. The results of CO2 flux measurement of each of the land uses on Andosol indicate that CO2 flux from vegetable garden and forest were almost similar, about 4,26 g C- CO2 m-2 d-1 and 4,28 g CO2 m-2 d-1, while that of bare land showed smaller results, about 2,01 g C- CO2 m-2 d-1. The results of analysis of soil respiration showed the same thing that is CO2 produced from soil of vegetable garden and forest is higher than that of bare land. These results are resembled by the results of the analysis of microbial populations in the soils of vegetable garden and forest that were higher than that of the bare land.</p><p><br />Keywords: Agricultural land, Andosol, CO2 flux</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17700 Sun, 01 Jan 2017 00:00:00 +0700 ANALISIS RUANG TERBUKA HIJAU DAN KECUKUPANNYA DI KOTA DEPOK https://journal.ipb.ac.id/index.php/btanah/article/view/17701 <p>Greenery open space (GOS) is a vegetated open space in urban areas, which its existence is often sacrificed in city development process. This study aims to determine acreage of GOS changes in Depok, to analyze the adequacy of GOS based on population, to identify level of development of the city, to analyze relationship between GOS changes and level of city development, and to identify factors affecting GOS changes. The results showed that in 2006 the GOS in Depok city was 2.359,20 ha and 1.729,53 ha in 2011 or it was a decline at about 629,67 ha during the period. Based on population number, Depok required 3.627,23 ha of GOS. Scalogram analysis indicated an increase in hierarchy of some subdistricts to level II and level I, and reducing of level III. The greatest changes of GOS occurred in the lower level of hierarchy (Level-III). This is due to limited land available for construction of facilities that are often sacrificed GOS. Determinants factors of GOS changes consisted of positive determinant, including acreage of vacant land, and negative factors, i.e. area allocated for built up in the regional spatial plan and initial acreage of GOS (2006).</p><p><br />Keywords: Adequacy of GOS, Greenery open space (GOS), regional development</p> Copyright (c) 2017 Buletin Tanah dan Lahan https://journal.ipb.ac.id/index.php/btanah/article/view/17701 Sun, 01 Jan 2017 00:00:00 +0700