• Journal of The Korean Society of Agricultural Engineers
• /
• v.53 no.6
• /
• pp.67-74
• /
• 2011

The objective of this study was to compare concentrations of nutrients such as total nitrogen (TN), nitrate nitrogen ($NO_3$-N) total phosphorous (TP), and phosphate phosphorous ($PO_4$-P) in groundwater under paddy and upland fields, and surface water recharging from a rural mixed land-use watershed. Chinese cabbage and hot pepper were cultivated on the upland field plot. The TN concentrations in upland groundwater showed double peaks (4.7, 4.3 mg/L, respectively) in April 2009 shortly after fertilizer application, indicating that TN concentrations are greatly influenced by fertilization. However, the TN concentrations in paddy groundwater were always lower than 2.0 mg/L irrespective of fertilization. Whereas the mean concentrations of TN and $NO_3$-N in upland groundwater significantly (p<0.05) higher than those in surface water, the mean concentrations of TP and $PO_4$-P in upland groundwater were significantly lower than those in surface water. On the other hand, the mean concentrations of TN, $NO_3$-N, TP and $PO_4$-P in paddy groudwater were significantly (p<0.05) lower than those in surface water. The TN concentrations in upland groundwater were generally higher than those in surface water during early April to early December due to the effect of fertilization, but vice versa in the other periods. In contrast, the TP concentrations in upland groundwater were always lower than those in surface water due to the sorption of inorganic phosphorous by soil. Moreover, the TN and TP concentrations in paddy groundwater were always lower than those in surface water, and therefore paddy groundwater may dilute nutrient concentrations in surface water when paddy groundwater and surface water mix.

• Korean Journal of Soil Science and Fertilizer
• /
• v.46 no.1
• /
• pp.1-7
• /
• 2013

This study was to examine growth, carbon and nitrogen responses in foliage following forest fertilization in a red pine stand. Two types of fertilizer (N:P:K=113:150:37 kg $ha^{-1}$; P:K=150:37 kg $ha^{-1}$) were applied on late April 2011. Growth, carbon and nitrogen responses of foliage were monitored 3 times (July, September, November) after fertilization. Morphological growth responses (dry mass, leaf area, specific leaf area) with foliage age were not significantly (P > 0.05) affected by fertilizer application, while needle dry mass and leaf area of July were significantly lower in current-year-old than in one-year-old or two-year-old needles of September or November. Carbon concentration and content in foliage was little affected by fertilizer application compared with sampling month or needle age, while the NPK fertilizer produced high nitrogen concentration and content of foliage. The results indicate that nitrogen concentration and content in foliage may serve as an indicator of the nitrogen status by fertilization in a red pine stand.

• Asian-Australasian Journal of Animal Sciences
• /
• v.21 no.2
• /
• pp.214-219
• /
• 2008

An experiment was conducted to evaluate the effects of nitrogen (N) level on the dry matter (DM) yield, N concentration and oxalate content of some tropical grasses, namely Rhodesgrass (Chloris gayana), Guineagrass (Panicum maximum) and Sudangrass (Sorghum vulgare). Three levels of N as urea were applied (Standard- 260, $Standard{\times}2$- 540 and$Standard{\times}4$- 1,060 kg N/ha for Rhodesgrass; Standard- 380, $Standard{\times}2$- 770 and $Standard{\times}4$- 1,570 kg N/ha for Guineagrass and Sudangrass) in a completely randomized design and grasses were harvested twice at approximately two-month intervals. Dry matter yield tended to be higher with increased rate of N fertilizer in all species, while further additional N ($Standard{\times}2$ or $Standard{\times}4$) did not significantly (p>0.05) further increase DM yield, when compared with the Standard level of N fertilizer application. There was also a trend towards higher N concentration in plants as N fertilization increased in all species and it was increased significantly in Rhodesgrass and Sudangrass (p<0.05 or p<0.01, respectively). Further additional N ($Standard{\times}2$ or $Standard{\times}4$) application showed no significant (p>0.05) differences on oxalate content in plant tissue within species, when compared with the Standard level of N. The Rhodesgrass contained 0.11, 0.13 and 0.15% soluble oxalate and 0.23, 0.25 and 0.27% total oxalate with Standard, $Standard{\times}2$ and $Standard{\times}4$ level of N application, respectively. The Guineagrass contained 0.54, 0.50 and 0.42% soluble oxalate and 1.60, 1.56 and 1.45% total oxalate with Standard, $Standard{\times}2$ and $Standard{\times}4$ level of N application, respectively. The Sudangrass contained 0.06, 0.15 and 0.12% soluble oxalate and 0.22, 0.22 and 0.21% total oxalate with Standard, $Standard{\times}2$ and $Standard{\times}4$ level of N application, respectively The results from this study suggest that these grasses do not use further addition of N fertilizer ($Standard{\times}2$ or $Standard{\times}4$) to form high content of oxalate salts, when compared with the Standard level of N. In addition, the levels of oxalate present with these grasses are quite low as far as toxicity to animals is concerned.

• Asian Journal of Turfgrass Science
• /
• v.4 no.1
• /
• pp.5-11
• /
• 1990

Korean Lawn. Zoysia japonica Steud. is the type of a perennial warm-season turfgrass keeping green leaf color for 5 months from May to September in natural condition in Korea. This Studies were carried out to obtain the effects of N-P-K fertilization, regrowth capacity after mowing and chlorophyll contents on prolongation of the green leaf color period in Zoysia japonica Steud turfgrass areas. The results obtained are summarized as follows ; 1.The effects of nitrogen fertilizer application in Zoysia japonica Steud, turfgrass areas were affected on regrowth ability after mowing green color of leaf canopies and chlorophyll contents, respectively(P<.05) 2.A experimental plots which applied 51 g/m$^2$/10 weeks of N$_3$P$_1$K$_1$fertilizer, there were high significant effects on prolongation of the green leaf color period and the plots of phosphorus and potassium had additive effects. 3.Prolongation of the green leaf color period to the last of October was obviously possible by slow degrees in proportation to increment of the fertilizer. However, it is interpreted that more prolongation of the green period is impossible with N-P-K fertilization and irrigation treatments. unless the intermediate turfgrasses between $C_3$ and $C_4$plants must be found and bred.

• Korean Journal of Soil Science and Fertilizer
• /
• v.31 no.1
• /
• pp.16-24
• /
• 1998

To determine the optimum application of fertilizers for the cultivation of Chinese cabbage in plastic film house, twenty soils which contain different salts contents were taken from 4 different area of plastic film house cultivation, Youngdong. Boeun county, Cheongweon county, and Cheongju city. The dry weight and the amount of N. P, and K uptakes of Chinese cabbage in the plot of no fertilization were considered as the factors representing the fertility of the soil. And a difference of dry weight and the amounts of N, P, and K uptakes of plants between the plot of fertilization and no fertilization were considered as the factors representing the total effect of fertilizer and fertilizer N, P, and K effects. respectively. These factors of soil fertility and fertilizer effects were estimated by correlation and regression with soil tests in order to find the critical levels and recommended method for optimum fertilization of Chinese cabbage. Chinese cabbage transplanted in two soils, having the electrical conductivity of 9.3 and 15.2 dS/m, were not able to root due to the salts toxicity. The content of inorganic N, the electrical conductivity, and CEC were founded to have significant correlation with the factors of both the soil fertility and fertilizer effects for the cultivation of Chinese cabbage. To determine the weighting degree for the productivity and the fertilizer effects, the standardized partial regression coefficient was analyzed by regression among the factors of fertility, the fertilizer effects, and the soil tests. The coefficient for inorganic N($NH_4-N$ and $NO_3-N$) was obtained as the absolute value of 756-1871 and this value was extremely higher than those of other soil tests which was 0.07-4.11. These results suggested that the content of inorganic N is the best tests for the estimation of the productivity and the fertilizer effects for the cultivation of Chinese cabbage in plastic film house. The critical level of inorganic N($NH_4-N+NO_3-N$) estimated by Cate-Nelson split method for maximum productivity and zero point of fertilizer effect was 220 mg/kg for all the factors of estimation. These results suggested that no application of fertilizer N. P, and K is required at the critical level of inorganic N of soil. Consequently the optimum application of fertilizer N, P, and K for the cultivation of Chinese cabbage in plastic film house was possible to determine by the critical level of inorganic N of soil. The critical level of electrical conductivity was estimated as 2.8 dS/m by the same method.

• Journal of Korean Society of Forest Science
• /
• v.90 no.3
• /
• pp.306-313
• /
• 2001

The objectives of this study were to understand the physiological responses and resistance of red pine trees to ozone exposure in relation to nitrogen and phosphorus fertilization. Potted one-year-old seedlings of Pinus densiflora S. et Z. were exposed in an open-top chamber(OTC) to ozone at concentration of 0.12ppm for 3 hours daily for eight weeks with or without N and P fertilization alone or in combination. The OTC had dimensions of 2.0m in height and 2.5m in diameter, and the air in a control chamber was filtered with activated charcoal to maintain the ozone concentration below 0.02ppm. After eight weeks of ozone exposure, none of the seedlings showed any symptoms of visible injury on leaves. The seedlings fertilized with N and P in a control chamber showed 22 to 95% increase in total dry weight, and similar fertilizer effect was also noticed in an ozone chamber. Ozone treatment did not decrease the total dry weight, but increased shoot/root ratio by 14.5%. Ozone treatment increased sucrose content in the leaves by 23%, but decreased sucrose content in roots by 20% regardless of N or P application. Starch content in the leaves was not affected by either ozone or fertilizer. However, starch content in the roots was decreased by 41% by ozone treatment. Chlorophyll content in the leaves was increased by 70% by N application, but was not affected by ozone treatment. Nitrogen and P fertilization stimulated net photosynthesis by 80% in a control chamber, but stimulatory effect of N and P on net photosynthesis was 22.3% less in an ozone chamber. Net photosynthesis of the seedlings with no fertilization was not affected by ozone treatment. Based on the observed interactions between N, P, and ozone, it was concluded that the stimulatory effect of fertilization on growth of Pinus densiflora would be decreased by ozone treatment, but fertilization would increase resistance to ozone by re-allocation of increased carbohydrates.

• Korean Journal of Soil Science and Fertilizer
• /
• v.45 no.1
• /
• pp.86-92
• /
• 2012

To promote the practical use of livestock manure compost (LC) for paddy rice cultivation, the fertilization efficiency of nutrients in LCs was investigated compared to that of chemical fertilizer. This experiment was conducted at rice field in Hwaseong, Korea, with 6 treatments by each of 3 kinds of tested LCs, cattle manure compost (CaC), swine manure compost (SwC) and chicken manure compost (ChC). The treatments consisted of 3 application levels of LCs and 3 chemical fertilizer treatments having the same application levels with LCs. $NH_4$-N content in soil became higher according to the increase in the urea application rate, while it became lower in LC plots than in urea plots, and statistically had no significant difference among LC plots. There was a close relationship between phosphate fertilization rate and the increment of soil available phosphate content after experiment resulting y = 0.1788x - 6.169 ($R^2=0.9425$) when applied fused superphosphate fertilizer, and y = 0.0662x - 2.689 ($R^2=0.9315$) when applied LC at the equivalent rates to phosphate input (x: phosphate application rate, kg $ha^{-1}$, y: increment in soil available phosphate content, mg $kg^{-1}$). And from these two equations, the correlation on the phosphate application rate between fused superphosphate fertilizer and LC could be obtained as y = 2.7056x - 52.492 (x: $P_2O_5$ application rate of fused superphosphate, kg $ha^{-1}$, y: $P_2O_5$ application rate of LC, kg $ha^{-1}$). Plant height, number of tillers, nutrients uptake by rice, and rice yield showed higher levels in N 100% and N 150% application plots of chemical fertilizers, while every LC plots exhibited lower values and no significant difference among them. Relative nitrogen fertilization efficiencies of LCs compared to urea was 12.3% for CaC, 8.8 for SwC and 24.6 for ChC, respectively.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.14 no.4
• /
• pp.307-315
• /
• 1994

The object of this experiment was to suggest the suitahle N-P-K fertilization level for orchardgrass(0G)-red clover(RC) mixtures under the intensive system of short-term pasture utilization. The fields trials were conducted over 3-year period(1991-1993) to evaluate dry matter yield. botanical composition, chemical composition and CP, DDM yield on the N-P-K levels (0-0-0. 50-100-100. 100-150-150, 150-2OO-200. 200-250-250 and 300-350- 350kg/ha). With increasing level of N-P-K, the DM yield of OG in the OG-RC mixture were significantly increased(P< 0.05), however, that of RC was remarkably decrcawd(P

• Asian-Australasian Journal of Animal Sciences
• /
• v.12 no.7
• /
• pp.1035-1039
• /
• 1999

Four ruminally cannulated buffalo bulls were fed mottgrass diets using a $4{\times}4$ Latin square design. Treatments were arranged factorially and consisted of mottgrass fertilized with 0 for Kg nitrogen (N) per acre and harvested at 40 and 60 days of age. Nitrogen fertilization improved the concentrations of neutral detergent fiber (NDF), and acid detergent fiber (ADF) in early-cut mottgrass (ECM) but, the acid detergent lignin (ADL) contents were higher in the late-cut mottgrass (LCM). The crude protein (CP) contents of the mottgrass decreased with advancing maturity, but N fertilization increased CP at both maturities. The intake of dry matter (DM), organic matter (OM), CP, NDF and ADF were higher by buffalo bulls fed ECM than those fed LCM. The ruminal pH increased in first 6 hours post feeding in animals fed N fertilized mottgrass and may be due to higher concentration of ruminal ammonia. The digestibilities of DM, OM, CP, NDF and ADF were higher by buffalo bulls fed ECM than those fed LCM. However, the application of N fertilizer did not affect the digestibilities of these nutrients.

• Korean Journal of Soil Science and Fertilizer
• /
• v.31 no.4
• /
• pp.350-358
• /
• 1998

To determine the optimum application of fertilizers for the cultivation of tomato in plastic film house, eighteen soils which contained different salt contents were taken from four different areas under plastic film house cultivation, Youngdong, Boeun, Cheongweon county, and Cheongju city. The dry weight and the amount of N, P, and K uptakes of tomato in the plot with no fertilization were considered as the factors representing the fertility of the soil. The differences in the dry weight and in the amounts of N, P, and K uptakes of plants between the plots with fertilization and with no fertilization were considered as the factors representing the total effect of fertilizer and the effects of fertilizer N, P, and K, respectively. These factors of soil fertility and fertilizer effects were estimated by correlation and regression with the chemical properties of the soil in order to find the critical levels and recommended method for optimum fertilization of tomato. The standardized partial regression coefficients of inorganic nitrogen ($NO_3-N+NH_4-N$) contents in soil for the factors of fertility ranged from 247 to 1,159, showing the best, while those of the others ranged from 0.02 to 4.02. Those of inorganic nitrogen ($NO_3-N+NH_4-N$) contents in soil for the electrical conductivity were also the best and were ranged from 35.2 to 36.0 compared with the values of less than 1.0 of the others. These results demonstrate that the content of inorganic nitrogen in the soil is the best index for both soil fertility and electrical conductivity of the soil. The critical level of inorganic nitrogen ($NO_3-N+NH_4-N$) in the soil for maximum productivity with zero value of fertilizer effects for tomato, estimated through Cate-Nelson split method was $220mg\;kg^{-1}$. This was the same value as evaluation for the cultivation of chinese cabbage. In conclusion, for optimal application of fertilizer in plastic film house, 1) no fertilization is recommended when the contents of inorganic nitrogen in the soil is more than $220mg\;kg^{-1}$; however, 2) in the case of less than $220mg\;kg^{-1}$ of inorganic nitrogen content in the soil, the optimal level of fertilization could be estimated through the regression equation between fertilizer effects and content of inorganic nitrogen in the soil.