• Korean Journal of Soil Science and Fertilizer
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• v.42 no.1
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• pp.1-13
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• 2009

Understanding the net nutrient balance in a farming system is crucial in assessing the system's sustainability. We quantified N, P and K balances under vegetable organic farming in a Eutric Haplud and in West Java, Indonesia in five planting seasons from 2005 to 2007. The ten treatments and three replications, arranged in a completely randomized block design, included single or combined sources of organic fertilizers: barnyard manure, compos ts or green manures. The organic matter rates were adjusted every planting season depending on the previous crop responses. The result sshowed that the application of ${\geq}20$ t $ha^{-1}$ barnyard manure per crop resulted in positive balances of N, P, and K, except in the second crops of 2006 where potassium balance were -25 to -11 kg $ha^{-1}$ under the treatments involving cattle barnyard manure, because of low K content of these treatments and high K uptake by Chinese cabbage. Application of 20 to 25 t $ha^{-1}$ of plant residue or 5 t $ha^{-1}$ of Tithonia compost also resulted in a negative K balance. Soil available P increased significantly under ${\geq}25$ t $ha^{-1}$ barnyard manure and that under chicken manure had the highest available P. Accordingly, chicken barnyard manure gave the highest crop yield because of relatively higher N, P, and K contents. Plant residues gave the lowest yield due to the lowest nutrient content among all sources. Reducing the use of barnyard manure to 12.5 t $ha^{-1}$ and substituting it with Tithonia compost, Tithonia green manure or vegetable plant residue compost gave insignificantly different yield compared to the application of 25 t $ha^{-1}$ barnyard manure singly. In the long run, application of 25 t ha-1 cattle, goat, and horse manure or about 20 t $ha^{-1}$ chicken manure is recommendable for sustaining the fertility of this Andisol for vegetable production.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.1
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• pp.1-10
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• 2016

The objective of this study was to investigate the effects of farming methods on mass balance from paddy rice. The experiment fields were established at Chunpo-myeon, Iksan-si in the Saemangeum watershed. Experiment was performed during the growing season to assess water and mass balances of the study field in 2013. The three different farming practices were applied: conventional (TR-A), drainage outlet heighten (TR-B) and slow release fertilizer use (TR-C). Drainage amount from TR-B was reduced by 28.5 % compared to the TR-A, while the amount from TR-C was similar to that of TR-A. Overall, nutrient concentration of paddy water were similar among the treatments except for T-P. Mean T-P concentration from TR-C was lower than that from TR-A (p-value<0.05). As the results of mass balance, TR-B appeared to reduce nutrient surface loss, substantially by 30.9 % and 40.8 % for T-N and T-P an compared to TR-A. TR-C treatment also demonstrated nutrient load reduction by 38.2 % and 40.1 % for T-N and T-P. The study results showed that water and fertilizer treatments are effective in surface load reduction respectively from paddy fields, and, long-term monitoring and evaluation is needed to confirm the reduction.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.12
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• pp.1674-1680
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• 2004

The objective of this study was to compare the Dutch DVE/OEB system and the NRC-2001 model in the prediction of supply of protein to dairy cows from processed field tick beans. Comparisons were made in terms of 1) ruminally synthesized microbial CP, 2) truly absorbed protein in the small intestine, and 3) degraded protein balance. The results showed that the predicted values from the DVE/OEB system and the NRC-2001 model had significant correlations with high R (>0.90) values. However, using the DVE/OEB system, the overall average microbial protein supply based on available energy was 16% higher and the truly absorbed protein in the small intestine was 9% higher than that predicted by the NRC-2001 model. The difference was also found in the prediction of the degraded protein balances (DPB), which was 5% lower than that predicted based on data from the NRC-2001 model. These differences are due to considerably different factors used in calculations in the two models, although both are based on similar principles. It need to mention that this comparison was based on the limited data, the full comparison involving various types of concentrate feeds will be investigated in the future.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.298-304
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• 2010

Nutrient uptake by plants and drainage ratio in culture beds can affect ion balance and concentrations of nutrient solutions in electrical conductivity (EC)-based closed-loop soilless culture. This study was conducted to analyze ion concentration changes with time and drainage ratio under EC-based nutrient control in closed-loop soilless culture for sweet pepper plants (Capsicum annum L. 'Boogie'). At first experiment, ion concentrations of the nutrient solution were periodically analysed while collected drainage was being reused by mixing with fresh nutrient solution at a dilution rate of EC $2.2\;dSm^{-1}$. Changes in ion concentrations of $K^+$, $Ca^{2+}$, $Mg^{2+}$, $NO_3^-$, $SO_4^{2-}$, and $PO_4^{3-}$ were 1.13, 5.35, 0.92, 0.9, 1.10, $0.19\;meq{\cdot}L^{-1}$, respectively. Ion balance such as $K^+$ : $Ca^{2+}$ and $SO_4^{2-}$ : $NO_3^-$ were mainly affected during the recirculation of nutrient solution. At second experiment, ion concentrations and EC of drainage were compared before and after replenishment under different four drainage ratios of 7%, 16%, 39%, and 51%. Ion ratios of the recirculated nutrient solutions such as $K^+$ : $Ca^{2+}$ for cation and $SO_4^{2-}$ : $NO_3^-$ for anion were investigated. ECs of drainage decreased with increase of drainage ratio and each ion concentration showed the same trends as EC did. Ion balances in drainage with drainage ratio were a little different from each other, but each ratio could be corrected by replenishment process. The ion balance at 7% drainage ratio was closest to initial ratio and followed by 16%, 51%, and 39% in the order. Ion balance such as $K^+$ : $Ca^{2+}$ and $NO_3^-$ : $PO_4^{3-}$ were mainly affected the correction process.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.1
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• pp.19-22
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• 2000

Twenty male crossbred calves of about one year of age (average body weight, 196 kg) were distributed in four equal groups following complete randomized design. Wheat bran was supplemented to four different combinations of wheat straw and green fodder (Sorghum vulgare) at 40:60, 30:70, 20:80 and 10:90 ratios (on as fed basis) for the feeding of animals in Group 1, 2, 3 and 4, respectively. The feeding trial was continued for a period of 70 days including one metabolism trial of 6 days collection of feed, faeces and urine sample to determine the intake and utilization of nutrients. The intakes (g/kg $W^{0.75}$) of DM, TDN and CP were $93.0{\pm}1.8$, $55.5{\pm}1.1$ and $9.51{\pm}0.18$ in Group 1; $98.0{\pm}1.8$, $59.6{\pm}1.1$ and $10.33{\pm}0.19$ in Group 2; $98.1{\pm}2.4$, $60.5{\pm}1.5$ and $10.79{\pm}0.26$ in Group 3; and $97.7{\pm}1.7$, $59.1{\pm}1.0$ and $10.78{\pm}0.19$ in Group 4, respectively. The digestibility of nutrients did not differ significantly among the groups. Relatively higher nutrient intake and balances of nitrogen reflected non-significantly high her live weight gain in the later three groups (436, 439 and 464 g, respectively) as compared to Group 1 (400 g). The DM intake remained unchanged by increasing the proportion of green fodder beyond 20:80 ratio and thus was assessed to be satisfactory for optimum productivity in animals.

• Journal of the Korean Society of Groundwater Environment
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• v.2 no.1
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• pp.14-21
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• 1995

Colloids such as exogenous biocolloids in a bioremediation operation can enhance the transport of contaminant in ground water by reducing retardation effects. Because of their colloidal size and favorable surface conditions in addition to their low density, bacteria can act as efficient contaminant carriers. When mobile bacteria are present in a subsurface environment, the system can be treated as consisting of three phases: water phase, bacterial phase, and the stationary solid matrix phase. In this work, a mathematical model based on mass balances is developed to describe the facilitated transport and fate of a contaminant in a porous medium. Bacterial partition between the bulk solution and the stationary solid matrix, and the contaminant partition among the three phases are represented by the equilibrium relationships. Solutions were obtained to provide estimates of contaminant and bacterial concentrations. A dimensionless analysis of the transport model was utilized to estimate model parameters from the experimental data. The model results matched with experimental data of Jenkins and Lion (1993). The presence of mobile bacteria enhances the contaminant transport. However, bacterial consumption of the contaminant which serves as a bacterial nutrient, can attenuate the contaminant concentration.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.7
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• pp.967-973
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• 2000

A metabolism trial was conducted with 28 Najdi rams allocated into seven dietary groups to evaluate the effect of dietary inclusion of Salicornia bigelovii Torr biomass on nutrient digestibility, rumina I fluid metabolites and nitrogen and mineral balances. Either the stems (ST) or spikes (SP) of this seawater-irrigated halophyte were incorporated into complete diets at rates of 0, 10, 20 and 30% levels, replacing equal amounts of rhodesgrass hay in a ground mixed control diet. Digestibility of DM, OM, EE, NFE and fecal and urinary nitrogen were not affected by increased level of ST in the diet. As level of ST increased from 0 to 20% in the diets, CP digestibility and nitrogen retention approached their maximum (p<0.01), whereas CF digestibility reached its minimum (p<0.01). On the other hand, except for EE, digestion of all nutrients and nitrogen retention were linearly depressed (p<0.01) as SP increased in the diets from 10 to 30% level. Concentration of ammonia-N, total VFA and pH values in the rumen fluid were lower (p<0.01) with the ST- or SP-fed diets than with the control diet. Increasing level of ST or SP in the diet was associated with an increase (p<0.01) in the proportion of acetate and a decline (p<0.01) in molar percentage of propionate in the ruminal fluid. Sodium absorption increased (p<0.01) with increased ST and SP in the diets up to the 10 and 20% level, respectively, followed by constant absorption values up to the 30% level. When the level of ST in the diet gradually increased to 30%, a concomitant increased (p<0:01) in Ca and P absorption were obvious; whereas, increased level of SP in the diets from 0 to 30% resulted in noticeable (p<0.01) depression in Ca and P apparent absorption.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.2
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• pp.216-224
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• 2009

In Japan, since rice consumption has been decreasing with the westernization of Japanese eating habits, surplus paddy fields have been increasing. If these surplus paddy fields can be utilized for forage rice production as feed for animal production and excretions (feces and urine) from animal production can be applied to the paddy fields as manure, then the problems of surplus paddy fields and excretions from animal production may be solved, and the environment kept sustainable. The objectives of the present study were to apply a bio-economic model to dairy and forage rice integration systems in Japan and to examine the merit of introducing whole crop rice silage (WCRS), as well as economic and environmental effects of various economic and management options in the systems. Five simulations were conducted using this model. The use of WCRS as a home-grown feed increased environmental loads and decreased economic benefit because of the higher amount of purchased feed, when compared to the use of typical crops such as maize, alfalfa and timothy silage (simulation 1). Higher economic benefits from higher forage rice yields and higher milk production of a dairy cow were obtained (simulations 2, 3). There were no economic and environmental incentives for utilizing crude protein (CP) rich WCRS, because an increase in the CP content in WCRS led to the use of more chemical fertilizers, resulting in high production costs and nitrogen outputs (simulation 4). When evaluated under the situation of a fixed herd size, increasing forage rice yields decreased the total benefit of the production, in spite of the fact that the amount of subsidies per unit of land increased (simulation 5). It was indicated that excess subsidy support may not promote yield of forage rice. It was, however, observed in most cases that dairy and forage rice integration systems could not be economically established without subsidies.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.8
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• pp.1068-1075
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• 2000

A study involving nutrient balances and radioisotope labeling techniques was undertaken to study energy and protein metabolism, and glucose kinetics of female crossbred Etawah goats, using 12 weaned (BW $14.0{\pm}2.0kg$), 12 late pregnant (BW $27.8{\pm}1.8kg$) and 12 first lactation does (BW $25.0{\pm}5.0kg$). Each class of animal was randomly allotted into 3 dietary treatment groups R1, R2 and R3, that received 100%, 85%, and 70% of ad libitum feed. The rations offered were pellets containing 21.8% CP and 19.3 MJ GE/kg, except for the lactating does who received pellets (17.2% CP and 18.9 MJ GE/kg) and fresh Penisetum purpureum grass. Energy and nitrogen balance studies were conducted during a two-week trial. Daily heat production (HP, estimated by the carbon dioxide entry rate technique), glucose pool and flux were measured. Equations were found for metabolizable energy (ME) and protein intake (IP) requirements for growing goats: ME (MJ/d)=1.87+0.55 RE-0.001 ADG+0.044 RP $(R^2=0.89)$ and IP (g/d)=48.47+2.99 RE+0.029 ADG+0.79 RP $(R^2=0.90)$; for pregnant does: ME (MJ/d)=5.92+0.96 RE-0.002 ADG+0.003 RP $(R^2=0.99)$ and IP (g/d)=58.34+5.41 RE+0.625 ADG-0.30 RP $(R^2=0.98)$; and for lactating does: ME (MJ/d)=4.23+0.713 RE+0.003 ADG+0.006 RP+0.002 MY $(R^2=0.86)$; IP (g/d)=84.05-5.36 RE+0.055 ADG-0.16 RP+0.068 MY $(R^2=0.45)$, where RE is retained energy (MJ/d), ADG is average daily gain in weight (g/d), RP is retained protein (g/d) and MY is milk yield (ml/d). ME and IP requirements for maintenance for growing goats were 0.46 MJ/d.kg $BW^{0.75}$ and 7.43 g/d.kg $BW^{0.75}$, respectively. Values for the pregnant and lactating does were in the same order, 0.55 MJ/d.kg $BW^{0.75}$ and 11.7 g/d.kg $BW^{0.75}$, and 0.50 MJ/d.kg $BW^{0.75}$ and 10.8 g/d.kg $BW^{0.75}$, respectively. Milk protein ranged from 3.06 to 3.5% and milk fat averaged 5.2%. Glucose metabolism in Etawah crossbred female goat is active, but glucose flux is low compared to temperate ruminant breeds which may implicate its role to support production.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.1
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• pp.46-52
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• 2004

Hisardale male lambs (n=24, 4-5 month of age) were maintained on a conventional ration for a month, to equilibrate the body mineral status. Six lambs were sacrificed after one month of feeding; the samples of organs were analyzed to ascertain mineral status. The remaining 18 lambs were divided into 3 groups of 6 each on body weight basis. Three dietary treatments containing 100 ($T_1$), 110 ($T_2$) and 120% ($T_3$) of minerals (Ca, P, S, Zn and Mn) as specified by NRC (1985) were formulated and each treatment was alloted ad libitum to a group for 120 days. Blood and wool samples were collected at monthly intervals. At the end of the experiment a balance trial of 5 days duration was conducted to study the balance of mineral elements. The effective intake of minerals was Ca, 111 and 120, P, 110 and 122; S, 112 and 129; Zn, 112 and 126 and Mn, 109 and 123 percent in $T_2$ and $T_3$, respectively, in comparison to $T_1$ (100). The additional mineral supplementation had no significant effect on dry matter intake. The average daily weight gain was higher (p<0.01) in $T_2$ and $T_3$ than the control ($T_1$). The lambs under treatments $T_2$ (8.72) and $T_3$ (8.47 kg) consumed apparently lesser amount of dry matter per unit gain as compared to $T_1$ (10.81 kg). Significantly higher (p<0.05) dry matter and crude protein digestibility (%) were observed in $T_2$ and $T_3$ than in $T_1$. The mean balances for different elements were Ca, 1.14, 1.68 and 1.67 g; P, 1.70, 1.95 and 2.18 g; S, 0.54, 0.92 and 1.11 g; Zn, 22.56, 25.30 and 28.71 mg; Cu, 7.94, 5.71 and 5.53 mg; Fe, 33.19, 32.94 and 31.03 mg and Mn, 8.24, 14.40 and 16.07 mg/lamb/day. The retention of supplemental minerals increased (p<0.01) while that of Cu decreased (p<0.01) due to supplementation of minerals (Ca, P, S, Zn and Mn). Retention as per cent of intake increased statistically for S and Mn while that of Cu decreased. It can be concluded that supplementation of minerals (Ca, P, S, Zn and Mn) higher than the recommended level improved body weight gain and feed to gain ratio. The retention of minerals increased due to supplementation. Therefore, an additional supplementation of deficient minerals (Ca, P, S, Zn and Mn) by 10% was beneficial for Hisardale male lambs under tropical condition in India.