Jurnal Tanah dan Iklim最新文献

{"title":"Estimated Stored Carbon Stock in Tea Plantation at Various Elevation","authors":"D. Rokhmah, N. Heryana","doi":"10.21082/jti.v45n2.2021.155-162","DOIUrl":"https://doi.org/10.21082/jti.v45n2.2021.155-162","url":null,"abstract":"","PeriodicalId":165570,"journal":{"name":"Jurnal Tanah dan Iklim","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124765830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dosis dan efek residu biochar kulit buah kakao dalam peningkatan sifat tanah dan produktivitas jagung di lahan kering masam Lampung Timur","authors":"Neneng Leila Nurida","doi":"10.21082/JTI.V45N2.2021.141-150","DOIUrl":"https://doi.org/10.21082/JTI.V45N2.2021.141-150","url":null,"abstract":"Dosis biochar yang diberikan ke dalam tanah menjadi aspek penting  dan merupakan salah satu faktor yang menentukan efektivitas pemberian biochar. Efektivitas biochar terlihat sangat nyata bila diapliksikan pada tanah-tanah di wilayah tropikal dibandingkan pada tanah di wilayah sub tropical. Penelitian ini bertujuan untuk mengetahui pengaruh beberapa taraf dosis biochar kulit buah kakao terhadap penurunan kemasaman tanah yang ditunjukkan dengan penurunan kemasaman tanah, peningkatan  kandungan hara makro dan hasil jagung di lahan kering masam terdegradasi. Penelitian dilaksnakan di Kebun Percobaan Balai Penelitian Tanah di KP Taman Bogo, Kecamatan Probolinggo, Kabupaten Lampung Timur. Penelitian dilaksanakan selama tiga musim tanam yaitu Pebruari-Mei 2015 (musim tanam pertama), Juli-Nopember 2015(musim tanam kedua) dan Nopember 2015-Pebruari 2016 (musim tanam ketiga). Penelitian menggunakan rancangan acak kelompok, 4  ulangan. Perlakuan yang diuji adalah dosis biochar kulit buah kakao 0; 5;10;15;25 dan 40 t ha -1 dan tanaman indikator berupa jagung varietas Pioneer 27.  Parameter yang diamati pH, P dan K , Ca, Mg dan Al 3+ serta berat pipilan kering. Hasil penelitian menunjukkan bahwa pemberian biochar kulit buah kakao dosis 15-40 tha -1 mampu memperbaiki sifat tanah seperti pH tanah, kandungan  Al 3+ kandungan P dan K potensial kandungan Ca dan Mg serta rasio Ca/Al. Respon paling konsisten terjadi pada pemberian biochar kulit bua kakao 40 t ha -1 .  Hasil jagung diperoleh dengan dosis mulai  15 t ha − 1 memberikan efek residu hingga musim ketiga, peningkatan hasil tertinggi terjadi pada musim tanam ketiga yaitu 32,9% (15 t ha − 1 ), 60,4% (25 t ha − 1 ) dan 61,3% (40 t ha − 1 ). Hasil jagung pipilan kering berkorelasi erat dengan kandungan Al 3+ (r 2 =0,8312; p< 0,001). Dosis biochar kulit buah kakao dengan dosis 15-40 t ha -1 sangat prospektif untuk ameliorasi lahan kering masam dan peningkatan produktivitas jagung, namun terdapat efek memudar dari sifat tanah pada musim tanam ketiga.","PeriodicalId":165570,"journal":{"name":"Jurnal Tanah dan Iklim","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131445199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pemetaan Indeks Kualitas Tanah (IKT) pada Lahan Tegalan di Kabupaten Jember","authors":"Ach Fauzan Mas'udi, I. Indarto, M. Mandala","doi":"10.21082/JTI.V45N2.2021.129-140","DOIUrl":"https://doi.org/10.21082/JTI.V45N2.2021.129-140","url":null,"abstract":"Lahan tegalan berpotensi sebagai salah satu alternatif dalam meningkatkan produksi tanaman. Fenomena yang terjadi saat ini adalah petani di lahan tegalan cenderung mengabaikan prinsip konservasi lingkungan. Indeks kualitas tanah (IKT) dapat digunakan untuk menilai dampak pengelolaan lahan. Penelitian ini dilakukan di lahan tegalan di Kabupaten Jember, Indonesia. Data yang dibutuhkan meliputi data jenis tanah, kelerengan, tata guna lahan, dan data analisis kualitas tanah. Analisis data menggunakan software SPSS 25.0, Excel 2016, dan Arc-MAP 10.4. Pemetaan kualitas tanah memiliki empat tahapan utama, (1) pembuatan petak satuan lahan, (2) analisis sifat tanah, (3) analisis komponen utama dengan metode PCA, dan (4) penilaian indeks kualitas tanah (IKT). Berdasarkan hasil analisis, terdapat tiga komponen utama dalam penilaian indeks kualitas tanah lahan tegalan yaitu karbon organik, lempung, dan pH. Lahan tegalan di daerah Jember terbagi menjadi tiga kelas, yaitu rendah (1,3%), sedang (63,9%), dan baik (34,7%). Secara umum kualitas tanah Tegalan di Kabupaten Jember termasuk dalam kategori sedang. Rekomendasi pengelolaan untuk lahan tegalan adalah penambahan bahan organik.","PeriodicalId":165570,"journal":{"name":"Jurnal Tanah dan Iklim","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114074579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Karakteristik Lahan Bera Dengan Umur Berbeda dan Pengaruhnya Terhadap Dekomposisi Serasah di Manokwari, Papua Barat","authors":"Slamet Arif Susanto, Ibnul Qayim, Triadiati Triadiati","doi":"10.21082/JTI.V45N2.2021.113-128","DOIUrl":"https://doi.org/10.21082/JTI.V45N2.2021.113-128","url":null,"abstract":"Abstrak. Karakteristik umur lahan bera memiliki peran penting dalam pengembalian hara melalui proses dekomposisi. Penelitian dekomposisi serasah dan cadangan karbon pada beberapa umur lahan bera telah dilakukan di Manokwari, Provinsi Papua Barat dari Juli 2020 sampai Januari 2021. Penelitian bertujuan menganalisis proses dekomposisi in situ serasah daun vegetasi lokal pada beberapa umur lahan bera, serta mengukur cadangan karbon dari vegetasi masing-masing lahan bera. Setiap umur lahan bera dipasang sebanyak 18 kantung serasah yang masing-masingnya berisi 20 g serasah daun dari vegetasi lokal lahan bera. Sebanyak tiga kantung serasah diambil setiap bulan dari masing-masing umur lahan bera, kemudian dikeringkan hingga bobot kering konstan. Cadangan karbon biomassa vegetasi dianalisis menggunakan persamaan alometrik berdasarkan diameter pohon setinggi dada (dbh). Hasil penelitian menunjukkan bahwa kehilangan bobot serasah setelah 6 bulan dekomposisi pada lahan bera 5, 10, dan 15 tahun masing-masing mencapai 92,62%; 94,00%; dan 97,12%. Konstanta dekomposisi (tetapan kehilangan bobot serasah) pada lahan bera 5 dan 10 tahun tergolong rendah yakni 0,65 dan 0,94. Lahan bera 15 tahun memiliki konstanta dekomposisi yang tergolong sedang yakni 1,18. Cadangan karbon pada lahan bera 5, 10, dan 15 tahun masing-masing sebesar 7,57; 32,63; dan 141,33 ton/ha. Penurunan rasio C/N setelah 6 bulan dekomposisi pada lahan bera 5, 10, dan 15 tahun masing-masing sebesar 66,67%; 56,25%; dan 39,39%. Dekomposisi serasah pada lahan bera 5 tahun dipengaruhi oleh curah hujan, sedangkan pada lahan bera 15 tahun dipengaruhi oleh kelembapan tanah. Penelitian ini mengindikasikan bahwa umur lahan bera menyebabkan perbedaan komposisi vegetasi, sehingga berpengaruh pada proses dekomposisi dan banyaknya cadangan karbon. Abstract. The characteristics of the fallow land have an important role in the return of nutrients through decomposition process. Research on litter decomposition and carbon stock on different ages of fallow has been carried out in Manokwari, West Papua from July 2020 to January 2021. The aim of the study was to analyze the in situ decomposition process of leaves litterfall from local vegetation at several ages of fallow, and also measure the biomass carbon stock of each fallow land. A total 18 litterbags were installed, each containing 20 g leaves litterfall from the local vegetation of the fallow land. Three litter bags from each age fallow were taken every month and dried to constant mass. Biomass carbon stocks were analyzed using an allometric equation based on the diameter of the trees at breast height (dbh). The results showed that the litter mass loss at fallow 5, 10, and 15 years were 92.62%; 94.00%; and 97.12% respectively after 6-month decomposition. The slowest decay constants (constants of litter mass loss) were 0.65 and 0.94 at fallows 5 and 10 years respectively, whereas at fallow 15 years with k 1.18. Carbon stocks in fallow land of 5, 10, and 15 years","PeriodicalId":165570,"journal":{"name":"Jurnal Tanah dan Iklim","volume":"204 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133032255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Populasi Bakteri Penambat Nitrogen pada Lahan Sub Optimal di Kabupaten Situbondo, Jawa Timur","authors":"M. Mandala, A. Rachmawati, Putri Tunjung Sari, I. Indarto","doi":"10.21082/JTI.V45N2.2021.15-22","DOIUrl":"https://doi.org/10.21082/JTI.V45N2.2021.15-22","url":null,"abstract":"Abstrak. Lahan sub optimal merupakan lahan yang memiliki produktivitas rendah. Lahan sub optimal terbagi menjadi lahan basah dan lahan kering. Rendahnya hara menjadi faktor pembatas dalam pengembangan lahan kering menjadi wilayah pertanian. Nitrogen merupakan hara esensial yang sangat diperlukan tanaman. Penggunaan tanaman leguminosae yang mampu bersimbiosis dengan bakteri penambat nitrogen dapat meningkatkan ketersediaan nitrogen dalam tanah. Penelitian ini bertujuan untuk mengetahui populasi bakteri penambat nitrogen dan hubunganya terhadap N-total tanah pada beberapa lokasi budidaya lahan kering. Penelitian dilakukan di lahan budidaya kacang panjang pada lima lokasi di Kabupaten Situbondo. Variabel Pengamatan meliputi : populasi bakteri penambat nitrogen, N-total, pH, C-organik dan C/N rasio. Hasil menunjukkan Lahan budidaya di Kecamatan Banyuglugur memiliki populasi bakteri dan nilai N-total tertinggi. Analisis korelasi regresi menunjukkan erdapat hubungan yang erat antara populasi bakteri penambat nitogen dengan N-total. Bakteri penambat nitrogen mempengaruhi ketersediaan nitrogen sebesar 61,72%, sedangkan 32,28 % dipengaruhi oleh faktor lain. Abstract. Sub optimal land has low productivity. Sub optimal land is divided into wetlands and dry lands. Low nutrients are a limiting factor in the development of dry land into agricultural areas. Nitrogen is an essential nutrient that is needed by plants. Legume plants can symbiosis with nitrogen fixing bacteria to increase the availability of nitrogen in the soil. This study aims to determine the population of nitrogen fixing bacteria and their relationship to soil N-total in several cultivation locations. The research was conducted in long bean cultivation at five locations in Situbondo Regency. Observation variables include: nitrogen fixing bacterial population, N-total, pH, C-organic and C / N ratio. The results showed that the cultivated land in Banyuglugur District had the highest bacterial population and N-total value. The regression correlation analysis showed that there was a close relationship between the nitogen-fixing bacterial population and total N. Nitrogen fixing bacteria affect nitrogen availability by 61.72%, while 32.28% was influenced by other factors.","PeriodicalId":165570,"journal":{"name":"Jurnal Tanah dan Iklim","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133354734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pencucian dan Pemupukan Tanah Sulfat Masam untuk Perbaikan Sifat Kimia dan Pertumbuhan Padi","authors":"Jelly Amalia Santri, Azwar Maas, S. Utami, Wahida Annisa","doi":"10.21082/JTI.V45N2.2021.1-14","DOIUrl":"https://doi.org/10.21082/JTI.V45N2.2021.1-14","url":null,"abstract":"Penelitian ini bertujuan untuk mengetahui pengaruh pencucian dan ameliorasi terhadap sifat kimia tanah dan air dalam menunjang pertumbuhan tanaman padi di lahan sulfat masam bukaan baru. Penelitian ini meliputi pembuatan kompos berbahan dasar tanaman lokal di kebun percobaan Belandean yang dilanjutkan dengan percobaan pot di rumah kaca Balittra Banjarbaru, Kalimantan Selatan pada bulan Februari sampai Mei 2019. Rancangan yang digunakan dalam penelitian ini adalah rancangan acak lengkap (RAL) faktorial 2 faktor dan diulang sebanyak 3 ulangan. Faktor pertama adalah pemupukan (P), yaitu: (a) P0 = tanpa dipupuk,  (b) P1 = pemupukan NPK 50% dosis rekomendasi, (c) P2 = pemberian NPK 50% dosis rekomendasi + Kompos, (d) P3 = pemberian NPK 100% dosis rekomendasi + NPK anorganik sesuai kandungan kompos, dan (P4) = pemberian NPK 100% dosis rekomendasi. Faktor kedua adalah pencucian (D) dengan sistem, yaitu: (a) D0 = air hasil pencucian tidak dikembalikan, (b) D1 = air hasil pencucian dikembalikan. Hasil penelitian menunjukkan bahwa pencucian dengan air hasil pencucian tidak dikembalikan membuat  nilai Eh, DHL serta kandungan Fe dan SO 4 tanah lebih rendah jika dibandingkan dengan perlakuan lainnya. Namun, nilai Al-dd dan H-dd tanah terendah terdapat pada perlakuan pengembalian air hasil pencucian dan pemupukan NPK 50% dosis rekomendasi dengan penambahan kompos bahan organik insitu . Perlakuan ini juga memiliki nilai produksi biomassa tertinggi jika dibandingkan dengan perlakuan lainnya.","PeriodicalId":165570,"journal":{"name":"Jurnal Tanah dan Iklim","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132116583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Penentuan Indeks Kesuburan Tanah di Sub DAS Dinoyo, Kabupaten Jember","authors":"Muhammad Rizal Romadhon, Bambang Hermiyanto","doi":"10.21082/JTI.V45N1.2021.27-37","DOIUrl":"https://doi.org/10.21082/JTI.V45N1.2021.27-37","url":null,"abstract":"Abstrak. Kurangnya informasi tentang kesuburan tanah suatu DAS menyebabkan penentuan penggunaan lahan yang tidak sesuai dengan tingkat kemampuan dan kesesuaian lahan. Penelitian ini bertujuan: (1) menentukan nilai dan kelas indeks kesuburan tanah di sub DAS Dinoyo Jember; (2) menentukan satuan peta lahan dengan kesuburan tanah tertinggi; (3) mengetahui urutan faktor penentu indeks kesuburan tanah dari yang berpengaruh hingga kurang berpengaruh. Penelitian ini dilakukan pada bulan Oktober 2019 - Februari 2020. Penelitian berupa survey tanah dengan metode purposive sampling pada 18 satuan peta lahan (SPL), setiap SPL diambil tiga sampel tanah yang telah dikomposit. Pengambilan sampel tanah dilakukan pada kedalaman 0-30 cm. Parameter yang diamati antara lain; KTK, C-Organik, N total, P tersedia, K dapat ditukar , Mg dapat ditukar, Ca dapat ditukar, dan Al dapat ditukar. Hasil analisis tanah digunakan untuk penilaian indeks kesuburan tanah. Hasil penelitian menunjukkan bahwa nilai indeks kesuburan tanah di sub DAS Dinoyo berkisar antara 130-170 yang dikategorikan dalam kelas agak rendah hingga sedang. Nilai indeks kesuburan tanah tertinggi (170) dengan kategori kelas sedang terdapat pada penggunaan lahan kebun dengan jenis tanah Latosol coklat kemerahan (Inceptisols) serta kemiringan lereng 25-40% (SPL 9) dan pada penggunaan lahan sawah dengan jenis tanah asosiasi Latosol coklat regosol kelabu (Inceptisols) serta kemiringan lereng 15-25% (SPL 14). Urutan faktor penentu indeks kesuburan tanah dari yang paling berpengaruh hingga kurang berpengaruh berturut-turut adalah kemiringan lereng, jenis tanah, dan penggunaan lahan. Abstract.  The lack of information about soil fertility of a watershed leads to improper land uses that did not correspond to the capability and suitability of the lands. This research aimed to: (1) determine value and class of soil fertility index in sub watershed Dinoyo, Jember; (2) determine land map unit (LMU) with the highest soil fertility; (3)  find out the sequence of determining factors of soil fertility index from the more influential to less influential. This research was conducted in October 2019-February 2020. Research in the form of soil sampling with purposive sampling method on 18 LU, in each LU we took three composite soil samples. Soil sampling was carried out at a depth of 0-30 cm. The observed parameters included; CEC, Organic C, Total N, available P, exchangeable K, Mg, Ca, and Al exchangeable. The results of soil analysis were used to determined soil fertility index. The results showed that the value of soil fertility index in sub watershed Dinoyo ranged from 130-170 categorized in rather low to moderate grades. The highest soil fertility index value (170) with medium grade category is found in garden with reddish brown Latosol (Inceptisol) soil type and slope of 25-40% (LMU 9) and on field with association of Brown Latosol-Gray Regosol (Inceptisol) soil type and slope of 15-25% (LMU 14). The sequence of determin","PeriodicalId":165570,"journal":{"name":"Jurnal Tanah dan Iklim","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125512963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Meningkatkan Kualitas Prediksi Curah Hujan Musiman saat Fase ENSO Menggunakan Metode Bayesian Model Averaging (BMA), Studi Kasus: Pulau Jawa","authors":"Robi Muharsyah, D. Ratri","doi":"10.21082/JTI.V45N1.2021.13-25","DOIUrl":"https://doi.org/10.21082/JTI.V45N1.2021.13-25","url":null,"abstract":"Abstrak. Ketika fase El Nino Southern Oscil l ation (ENSO), El Nino atau La Nina terjadi, Curah Hujan (CH) musiman di Pulau Jawa cenderung mengalami kondisi di Bawah Normal (BN) atau Atas Normal (AN). Oleh karena itu, prediksi CH musiman yang akurat menjadi sangat penting pada kedua fase tersebut. Model ECMWF System 4 (S4) adalah salah satu model prediksi musim yang dapat dipakai untuk menghasilkan prediksi probabilistik kejadian BN atau AN. Akan tetapi, kualitas dari keluaran langsung (RAW) model S4 masih buruk. Metode Bayesian Model Averaging (BMA) dipilih sebagai post-processing statistik untuk memperbaiki kualitas tersebut. Probability Density Function (PDF) prediktif BMA mampu menghasilkan prediksi deterministik dan probabilistik lebih akurat dari RAW model S4. Tingkat akurasi tersebut diketahui dari Root Mean Square Error (RMSE) dan Brier Score (BS) BMA lebih rendah dari RAW; RMSE Skill Score (RMSS), Brier Skill Score (BSS) dan Relative Operating Characteristic Skill Score (ROCSS) BMA lebih besar dari RAW, serta reliabilitas BMA menjadi kategori “sempurna” dan “sangat berguna” dari sebelumnya “tidak berguna” pada RAW model S4. Penerapan BMA mampu memperbaiki kualitas prediksi CH RAW model S4 sehingga prediksi CH musiman menjadi bermanfaat jika dipakai dalam pengambilan keputusan terkait kondisi iklim beberapa bulan ke depan, khususnya pada fase El Nino atau La Nina di Pulau Jawa. Abstract . When El Nino Southern Oscillation (ENSO), El Nino or La Nina phase is occurred, seasonal rainfall over Java Island tend to experience Below Normal (BN) or Above Normal (AN) conditions. Therefore, more accurate seasonal rainfall predictions are essential for both phases. The ECMWF System 4 (S4) is a seasonal prediction model which can be used to generate probabilistic predictions BN or AN event. However, the direct output (RAW) of S4 models such as rainfall prediction has poor quality. The Bayesian Model Averaging (BMA) is selected as one of the post-processing statistics to improve its quality. The predictive Probability Density Function (PDF) of BMA is able to produce deterministic and probabilistic prediction more accurately than RAW S4 models. The accuracy is known from Root Mean Square Error (RMSE), Brier Score (BS) BMA that is lower than RAW; RMSE Skill Score (RMSS), Brier Skill Score (BSS) and Relative Operating Characteristic Skill Score (ROCSS) BMA that is greater than RAW. Hence, the reliability of the BMA is changing to the “perfect” and “very useful” category from the previous “not useful” in RAW model S4. The implementation of BMA is able to improve the prediction quality of CH RAW model S4. As the result, seasonal rainfall prediction will be useful in making decisions related to climate conditions for the coming months, especially in the El Nino or La Nina phase over Java Island.","PeriodicalId":165570,"journal":{"name":"Jurnal Tanah dan Iklim","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116851810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efisiensi Pemupukan N Tanaman Jagung Manis akibat Beberapa Dosis dan Waktu Aplikasi Urea Menggunakan Teknik Isotop 15N","authors":"Anggi Nico Flatian, Adinda Rachmadhani Febrianda, E. Suryadi","doi":"10.21082/JTI.V44N2.2020.93-100","DOIUrl":"https://doi.org/10.21082/JTI.V44N2.2020.93-100","url":null,"abstract":"Abstrak. Pemberian pupuk N dapat secara efektif meningkatkan hasil tanaman. Namun cara pemupukan N yang tidak tepat, dapat menyebabkan tidak efisiennya pemupukan. Penelitian ini bertujuan untuk mengetahui pengaruh dosis dan waktu aplikasi urea terhadap hasil, serapan dan efisiensi pemupukan N ( 15 N) pada tanaman jagung manis. Penelitian dilaksanakan pada bulan Maret sampai November 2018 di rumah kaca dan laboratorium. Percobaan pot menggunakan Rancangan Acak Kelompok pola Faktorial. Faktor pertama adalah dosis pupuk nitrogen yang terdiri dari 3 taraf perlakuan: (1) urea sebesar 60 ppm N, (2) urea sebesar 70 ppm N, dan (3) urea sebesar 80 ppm N. Faktor kedua adalah waktu aplikasi: (1) dua kali, (2) tiga kali, dan (3) empat kali. Hasil penelitian menunjukkan bahwa sebagian besar (50,7-54,4 %) N yang diserap tanaman jagung berasal dari pupuk urea (%Nbdp), sisanya (49,3-47,6 %) berasal dari tanah (%Nbdt). Pemupukan urea dosis 60 ppm N (ekivalen dengan 250 kg ha -1 ) menyebabkan efisiensi pemupukan N tertinggi (82,7%). Nilai efisiensi pemupukan secara signifikan menurun seiring peningkatan dosis urea, tetapi tidak berpengaruh nyata terhadap bobot hasil. Dosis urea juga berpengaruh signifikan terhadap nilai %N tanaman berasal dari pupuk (%Nbdp) dan %N tanaman berasal dari tanah (%Nbdt). Sedangkan waktu pemupukan hanya berpengaruh terhadap %Nbdp dan %Nbdt. Efisiensi pemupukan N tanaman jagung pada penelitian ini adalah sebesar 55,6-82,7 %. Hal ini berarti sebagian besar pupuk urea ( 15 N) yang diaplikasikan telah diserap oleh tanaman. Abstract. Application of N fertilizers can effectively increase crop yields. However, improper fertilization management, can cause inefficient fertilization. This study was conducted to evaluate the effect of rates and split application of urea on yield, N uptake and fertilizer N ( 15 N) use efficiency  (FNUE) of sweet corn plants. The study was conducted from March to November 2018 at the greenhouse and laboratory. The pot experiment was designed using Factorial Randomize Block Design. The first factor was urea fertilizer dose: (1) 60 ppm N, (2) 70 ppm N, and (3) 80 ppm N. The second factor was split of application: (1) two times, (2) three times, and (3) four times. The results showed that most (50.7-54.4 %) of the N absorbed by corn plants came from urea fertilizer (%Ndff),  and the rest (49.3-47.6 %) came from soil (%Ndfs). The rate of 60 ppm N (uquivalent to 250 kg ha -1 urea) caused the highest (82.7%) FNUE. The FNUE value significantly decreased with increasing dose of urea, but did not significantly affect the dry weight yield. The rate of urea also has a significant effect on the value of %N derived from fertilizer (%Ndff) and %N derived from soil (%Ndfs). Meanwhile, splitting fertilization time only significantly affected %Ndff and %Ndfs. In general, fertilizer N use efficiency in this study was between 55.6% with 82.7%. This means that most of the urea ( 15 N) fertilizer applied has been absorbed by plants.","PeriodicalId":165570,"journal":{"name":"Jurnal Tanah dan Iklim","volume":"109 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127094126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pengaruh Amelioran Partikel Nano Batuan Fosfat dan Jamur Pelarut Fosfat terhadap Sifat Kimia Inceptisols Cilembu, Jawa Barat","authors":"Fajri Syahid Nurhakim, P. Suryatmana, Muhammad Amir Solihin, Rina Devnita, M. Arifin","doi":"10.21082/jti.v44n2.2020.155-162","DOIUrl":"https://doi.org/10.21082/jti.v44n2.2020.155-162","url":null,"abstract":"Abstrak. Inceptisols Cilembu memiliki potensi besar untuk pertanian khususnya untuk budidaya ubi jalar Cilembu. Rendahnya kandungan P-tersedia yang merupakan unsur hara esensial berdampak pada produktivitas tanah. Aplikasi amelioran partikel nano batuan fosfat dan Jamur Pelarut Fosfat (JPF) memiliki kemampuan dalam meningkatkan P-tersedia Inceptisols Cilembu. Penelitian ini bertujuan untuk mengkaji pengaruh amelioran partikel nano batuan fosfat dan JPF terhadap beberapa sifat kimia Inceptisols di sekitar Cilembu. Metode penelitian menggunakan Rancangan Acak Lengkap Faktorial. Faktor pertama yaitu amelioran partikel nano batuan fosfat yang terdiri atas empat taraf, yaitu b 0 = 0% (0 g), b 1 = 2% (20 g kg -1 tanah), b 2 = 4% (40 g kg -1  tanah), dan b 3 = 6% (60 g kg -1 tanah). Faktor kedua yaitu JPF yang terdiri atas dua taraf, yaitu h 0 = (0 g) dan h 1 = JPF (10 g per kg -1 tanah). Parameter yang diamati: pH, P-tersedia, Kapasitas Tukar Kation (KTK), dan populasi JPF. Data hasil pengamatan dianalisis menggunakan analisis varians pada taraf 5%, dilanjutkan dengan uji beda jarak Duncan pada taraf 5%. Hasil analisis varians menunjukkan tidak terdapat interaksi antara amelioran partikel nano batuan fosfat dan JPF terhadap parameter yang diamati. Aplikasi amelioran partikel nano batuan fosfat berpengaruh nyata dalam meningkatkan pH dan P-tersedia. Penggunaan JPF berpengaruh nyata meningkatkan nilai KTK. Abstract. Inceptisols in Cilembu have a great potential for agriculture, especially for sweet potato cultivation. The low available P content, which is an essential nutrient, has an impact on soil productivity. The application of nano particle phosphate rock ameliorant and Phosphate Solubilizing Fungi (PSF) may increasing available P of Inceptisols in Cilembu. The research aimed to find out the effects of nano particle phosphate rock ameliorant and PSF on selected chemical properties of Inceptisols in Cilembu area. The research method used Factorial Completely Randomized Design. The first factor was ameliorant nano particles of phosphate rock application consisted of four levels, namely b 0 = 0% (0 g), b 1 = 2% (20 g kg -1 of soil), b 2 = 4% (40 g kg -1 of soil), b 3 = 6 % (60 g kg -1 of soil). The second factor was PSF treatment consisted of two levels, namely h 0 = without PSF and h 1 = PSF 10 g kg -1 of soil. Parameters observed were pH, available P, Cation Exchange Capacity (CEC), and PSF population. The data were analyzed with analysis of variance at the significance level of 5%, and continued with Duncan multiple range test at the significance level of 5%. The results showed that there was no interaction between ameliorant nano particles of phosphate rock application and PSF inoculation on the observed parameters. The application of ameliorant nano particles of phosphate rock significantly increased soil acidity (pH) and available P. The inoculation of PSF significantly increased the CEC.","PeriodicalId":165570,"journal":{"name":"Jurnal Tanah dan Iklim","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128546652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}