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The study entitled "Chromolaena odorata Compost Affected Soil Chemical and Rice Crop (Oryza sativa L.) had been conducted in Padang City, West Sumatra. It was started in February 2015 to May 2015. The study aimed was to examine the mechanism of amendment soil chemical properties and nutrient uptake of rice crop was fertilized By Chromolaena odorata Compost. The experiment was conducted by using Randomized Complete Design (RCD) in Split Plot Design with the main plots were three varieties of rice crops namely; Cisokan (V1); Pandan Wangi (V2) and Red Cempo (V3). The subplot consisted three types of fertilizer composition; 5 Mg ha -1 Compost C. odorata (CCP) +100% Artificial Fertilizer Recommendation (AFR) (F1); 7.5 Mg ha -1 CCP+75% AFR (F2); 10 Mg ha -1 CCP +50% AFR (F3), with three replications. Data was analysed by using the F test significance level of 5%, and an Honestly Significant Difference test (HSD) α 5%. Parameters include analysis of soil chemical properties, manure, analysis of nutrient uptake and the weight of dry crop biomass. The study indicated there was amendment in soil chemical properties after the application of C. odorata, compost achieving optimal fertility for rice crop. Nitrogen and other minerals uptake in rice crop increased due to the increased provision of artificial fertilizers escorted by lowering the dose of C.odorata compost. The ability about the nutrient uptake of rice crop is higher in rice Pandan Wangi and causes the higher forage yield than rice Cisokan or Red Cempo.

Manggis memiliki potensi di bidang ekonomi, data statistik tahun 2015 menunjukkan bahwa ekspor manggis mencapai nilai USD 17.2 juta. Kecamatan Pauh dipilih sebagai sentra pengembangan perkebunan manggis di Kota Padang. Pengembangan ini harus didasari dengan kesesuaian lahan sehingga tanaman manggis dapat tumbuh selaras dengan iklim dan kondisi lahan. Penelitian ini dilaksanakan di Kecamatan Pauh Kota Padang. Metoda yang digunakan dalam penelitian ini adalah metoda survei dengan beberapa tahapan yaitu persiapan, pra survei, survei utama, analisis di laboratorium, dan pengolahan data. Evaluasi kesesuaian lahan dilakukan dengan metoda matching yaitu membandingkan nilai kualitas dan karakteristik lahan dengan persyaratan tumbuh tanaman. Berdasarkan hasil penelitian, didapatkan kesesuaian lahan untuk tanaman manggis diklasifikasikan ke dalam kelas sesuai marjinal (S3) dengan sub kelas S3nr untuk SL1,2,3,4,7,8,9,11,15; sub kelas S3nr,eh untuk SL5 dan SL10; subkelas S3eh untuk SL14. Namun, pada satuan lahan SL6,12,13, dan 16 didapatkan kelas kesesuaian cukup sesuai (S2) dengan subkelas S2wa,nr untuk SL6 dan SL16; S2wa,rc,nr,eh untuk SL12; dan S2wa,rc,nr untuk SL13. Faktor pembatas yang umum pada masing-masing lahan adalah retensi hara (nr) dan bahaya erosi/lereng (eh). Terdapat 3 kelurahan (Lambung Bukit, Limau Manis, dan Limau Manis Selatan) di Kecamatan Pauh yang memiliki potensi paling besar untuk dikembangkan sebagai wilayah pengembangan perkebunan manggis dengan total luas 5,862 ha.

The Rubber plantation area is an agroforestry cover area that resembles a forest cover area. Recently, there have been many land conversions, both from forests to intensive agricultural areas, agroforestry to intensive agricultural areas. Land conversion is mostly carried out by the slash-and-burn method with negative impacts causing land degradation. This study was aimed to determine changes in several parameters of chemical properties on land that has undergone burning. This research had been conducted from April to August 2022 in Nagari Padang Laweh, Koto VII District, Sijunjung Regency. Then continued at the Soil Chemistry Laboratory of the Faculty of Agriculture, Andalas University. Soil samples were taken from three land uses, namely, Rubber fields, former Rubber plants that had been cut down and former Rubber plants that had been planted with Corn on the same slopes. The data obtained from the results of the analysis were processed using microsoft excel and read with a table of criteria for soil chemical properties. The results showed a decrease in several parameters of soil chemical properties on land that was converted by the slash-and-burn method. After the land was planted with food crops, there was an increase in some of the parameters of chemical properties studied.

Sorghum is a dry land food crop that has great potential developed in Indonesia. The results proved that sorghum is the most appropriate crop of choice in an effort to increase the productivity of dry land that is acid, empty land or other non-productive land such as mining land that has been done by PT. Semen Tonasa in 2012.While Juniarti in 2009- 2011 has been planting sorghum on the soil of Andisol, Entisol and Regosol in two seasons; winter and summer at Shobara, Hiroshima Perfecture Japan. The planted sorghum can produce biomass that can be utilized as an energy source used for the cultivation of strawberries in greenhouses and the utilization of energy in the household scope of Shobara-Hiroshima. The development of sorghum, the land productivity will be increased and support the development of sustainable agriculture and the increased of Indonesian food production. Through the research collaboration that has been done with PT. Agro Indah Permata 21 since 2015 has been planting sorghum in Padang Laweh, Koto VII District Sijunjung Regency, West Sumatera Indonesia with planting area of proximate 8 T/Ha and has produced production of 10 T/Ha of wheat seeds. The results of planting sorghum that has been done to produce sorghum seed products that have been processed into flour and sugar products from the stem of sorghum as a supplement due to outbreak of COVID-19. By evaluating land characteristics appropriate for the development of sorghum plants, in Padang Laweh, West Sumatra Indonesia.