An integrated farming system is one of the alternatives for climatic change mitigation. This paper reports the application of corn-cattle based integrated farming system in Agrotechno Park Center of Palembang, and discusses its impact on CO 2 fixation and the reduction of methane emissions. The study was based on the data of the first 6 yr from 2003 until 2009. The CO 2 fixed in the soil and plants was determined based on the content of organic C which was multiplied by the index of 3.67. The methane gas produced by Balinese cattle and its dung was observed and modified into feed rations. The results showed that soil organic C increased from 40.80 tons C/ha in the 1 st yr to 66.40 tons C/ha in the 6 th yr. In addition, there was organic C fixation equivalent to 93.95 tons of CO 2 e. Corn biomass increased from 6.67 tons/ha to 18.66 tons/ha, equivalent to an increase in the fixation of atmospheric CO 2 e as much as 19.80 tons CO 2 e/ha. The supplementation of 60%-80% grass fodder with concentrate lowered the concentration of methane gas in cattle breathing by 28.7%, from 617 ppm to 440 ppm, while the methane emissions from cattle manure decreased by 31%, from 1367 mL/head/d to 943 mL/head/d. Installing a bio digester that generates biogas served to accommodate methane gas emissions from cattle dung and used it for bioenergy. Composting reduced the formation of methane gas from cattle manure through a regular process of turning over that gives aeration and forms aerobic condition in the heap of cattle dung. Recycling produces a variety of organic products that store carbon for a longer period of time and slowed the conversion of organic C into CO 2. This study showed that the diverse activities of an integrated crop-cattle farming could be an alternative solution to climatic change mitigation.

Kegiatan peternakan setidaknya menyumbangkan 24,1% dari dari total emisi yang berasal dari sektor pertanian. Emisi yang berasal dari peternakan bersumber dari aktivitas pencernaan dan pengelolaan kotoran berupa gas CH4 (metana) yang dampaknya 21 kali lebih berbahaya dibandingkan dengan CO2. Pemilihan jenis pakan akan sangat mempengaruhi sumbangan gas rumah kaca dari kegiatan peternakan. Pakan ternak ruminansia dapat berupa hijauan (rumput-rumputan) ataupun konsentrat/ ransum. Salah satu caramenurunkan produksi CH4 dalam kegiatan peternakan dengan meningkatkan daya cerna pakan yaitu menambah jumlah konsentrat dalam pakan. Penelitian ini bertujuan untuk menentukan komposisi pakan perbandingan rumput dan konsentrat untuk ternak sapi yang dapat mereduksi gas metana (CH4) dan menganalisis besaran konversi feses ternak sapi menjadi biogas dan metana pada paka tersebut. Penelitian ini dilakukan dengan rancangan Acak Kelompok (RAK) non faktorial dengan 5 perlakuan dan 5 ulangan, perlakuan pakan yang di berikan yaitu A (100 % pakan hijuan), B (80% rumput + 20% Ransum), C (60% rumput + 40% Ransum), D (40% rumput+60% ransum), dan E (20% rumput +80% hijuan). Peubah yang diamati adalah konsentrasi metana dari pernafasan, volume biogas, konsentrasi metana dari biogas. Hasil penelitian menunjukkan pemberian pakan ternak sapi dengan komposisi 80% konsentrat dan 20% hijauan (perlakuan E), akan dihasilkan gas metana dari pencernaan paling rendah, dengan pakan tersebut feses ternak akan dihasilkan volume biogas yang paling banyak. Biogas paling sedikit terdapat pada pelakuan 40% konsentrat+60% hijaun (perlakuan D). Feses ternak dengan pakan hijauan (Perlakuan A) saja akan menghasilkan gas metan paling banyak.Kata kunci : Komposisi pakan, konsentrat, metana (CH4), reduksi

Calcium (Ca) is one of the essential macrominerals needed by the human body as a major component in the formation of bones and teeth. Calcium is fulfilled by eating calcium-rich foods, both animal and vegetable. Mustard and lettuce are vegetables that can be a source of Ca. Efforts to increase the Ca content in plants can be done through increasing the concentration of Ca given through fertilizer or in nutrient solution. However, excessive Ca application is not recommended because it will be toxic to plants. This study aims to determine the effect of various Ca concentrations in hydroponic nutrient solutions on the growth and yield of mustard vegetables (Brassica juncea L) and lettuce (Lactuca sativa L.). This study used a floating hydroponic system with a completely randomized design. Treatment of Ca concentrations of hydroponic nutrient solutions that were tried were 0, 100, 200, 300, and 400 ppm. The parameters observed were plant height, number of leaves, level of greenness of leaves, fresh and dry weight, and concentration of calcium in the leaves. The results showed that Ca treatment significantly affected the number of leaves and the level of leaf greenness. Application of 400 ppm Ca in hydroponic nutrient solution is the highest Ca concentration that could increase Ca content in mustard and lettuce plants. Application of Ca 300 ppm is the highest concentration of hydroponic nutrient solution that can increase the Ca content of plants without causing a decrease in plant biomass, and therefore the treatment of Ca 300 ppm can be used for biofortification of Ca by hydroponic in mustard and lettuce plants.

Utilization of Citronella Waste as Animal Feed and Organic Fertilizer in Payakabung Village, Ogan Ilir Regency, South Sumatra Lemongrass is an essential plant that is easy to cultivate. Many farmers in Payakabung village cultivate it. There are 3 units of lemongrass essential refineries with a capacity of 2 tons per day, which produce 6 tons of citronella fragrant waste every day or 180 tons every month. The production of Citronella Waste is a problem in the area around the distillation plant, so a solution to this problem is needed. Utilization as animal feed and organic fertilizer is a solution that can be done, but the knowledge of farmers about the technology of utilizing citronella waste is still low, so it is necessary to carry out farmer assistance activities regarding the use of citronella waste as feed and organic fertilizer. activities carried out include coordination with the village government, training, discussion and evaluation. The results of this activity show the lack of knowledge of farmers about the use of citronella waste, the use of which is only done as mulch in rubber gardens. this activity increases the knowledge of farmers to use other citronella waste. This activity is expected to have an impact on reducing the citronella waste that has accumulated in Payakabung village.

Organic hydroponic cultivation systems require substitute nutrients other than inorganic fertilizers as a source of plant nutrients. Catfish cultivation waste is one of the potentials that can be used as hydroponic nutrients. This study aimed to find out the concentration of Liquid Organic Fertilizer (LOF) from fish cultivation waste as a substitute for commercial inorganic nutrients on the growth of pakcoy (Brassica rapa L.).  This research was carried out in 2 stages, namely the manufacture of LOF from catfish culture waste and experiments using LOF as hydroponic nutrients. The results of this study showed that the increase in LOF nutrient content in anaerobic fermentation was higher than in aerobic fermentation. The use of LOF as a hydroponic nutrient, based on the parameters of plant height, number of leaves, SPAD value, root weight, crown weight, and dry weight obtained a smaller value that was significantly different compared to the inorganic nutrient treatment of AB mix. LOF concentration of 20%, both fermented aerobically and anaerobically, gave better growth when compared to higher concentration treatments. The nutrient content in LOF is difficult to adjust to the needs of hydroponic pakcoy, so that it will have a toxic impact on macro nutrients on the other hand, it also provides a response to micro nutrient deficiency.

No abstract

This study aimed to compare cormels and suckers to determine the better planting material (PM) and to evaluate the effects of morphology-altering treatments on both shoot growth and corm yield in taro plants. The PMs used included cormel (PMC), suckers with two leaves (PMS2) and suckers with four leaves (PMS4). Morphological alteration (MA) treatment included removal of all suckers (MAS), excising the mother plant (MAM), and non-treated control (NMA). Data were collected weekly for non-destructive and at 12, 20, and 28 weeks after planting (WAP) for destructive measurements. Results of this study indicated that the SPAD values were higher in taro plants grown using cormel and morphologically non-altered plants. Removal of all suckers caused the mother plant to increase the number of leaves. The dry weight of the leaf blades, petioles and fibrous roots of the mother plant and the number of suckers decreased after the corm enlargement process took place. Fresh and dry weights of the corm increased at 20 WAP and then slowed down at 28 WAP. The moisture content of corm was relatively constant at 75%. Cormel could form on the fibrous roots and on suckers, but the total wet and dry weights of the cormels were decreased if the suckers were periodically removed. The growth of suckers was very dominant compared to the NMA plant when the mother plant was excised. Meanwhile, if all the suckers were removed, the growth of the mother plant was relatively comparable to that of the NMA plants.

Chaya (Cnidoscolus aconitifolius (Mill.) I.M. Johnst.) is a perennial leafy vegetable. Since the leaf blade is the most crucial component of the Chaya, it should be advantageous to estimate the leaf area non-destructively. This research aimed to (a) develop a beneficial non-destructive model for leaf area estimation, and (b) ascertain the impact of stem cutting diameter when used as planting material on chaya growth rate. The results demonstrated that utilizing the length x width (LW) of the middle lobe as the predictor and the zero intercepts linear regression LA = 1.679 LW with R2=0.947 determination coefficient was the most dependable model for Chaya plant leaf area estimation. The stem diameter, which ranged from 9.9 to 17.3 mm, had affected the shoot length, number of leaves, and canopy area between 5 and 7 weeks after planting (WAP). The variations in growth metrics diminished along with the age of plants. The diameter of the stem cutting used as planting material had no effect on the fresh weight of young edible shoot tip at 11 WAP. On Chaya plants that were cultivated with larger stem cutting diameters, the fresh leaf weight at the branch tips was heavier.