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1.
The transportation of dissolved organic nitrogen (DON) from croplands to aquatic ecosystems potentially negatively influences water quality. Sustaining crop yields while decreasing the environmental impacts of the DON from nitrogen fertilizer application is a key challenge in sustainable agriculture. However, few field datasets have measured the lateral transportation of DON via hydrological routes under different nitrogen fertilizer applications, particularly in sloping croplands. Using lysimeter plots (8?×?4 m2), we measured DON loss via overland flow, interflow, and soil erosion under different fertilizer applications under a long-term field experiment. There were four treatments, including no fertilizer (CK), mineral fertilizer (NPK), mineral fertilizer combined with swine manure (MNPK), and mineral fertilizer combined with crop straw (CNPK). In comparison to the NPK treatment, the annual DON loss fluxes via overland flow, interflow, and soil erosion for the MNPK treatment were significantly (P?<?0.05) increased by 68.8, 100.6, and 63.7%, respectively. Conversely, this was significantly decreased by 182.6, ??14.1, and 49.4%, respectively, under the CNPK treatment. Correspondingly, the yield-scaled total DON losses for the MNPK and CNPK treatments were significantly increased by 78.8 and ??18.2% compared to the NPK treatment (0.33?±?0.04 kg N t?1 grain). Therefore, long-term continuous manure application is associated with an increased risk of DON environmental pollution. Alternatively, the incorporation of crop straw can be recommended as a means of decreasing DON pollution while maintaining crop yield. 相似文献
2.
The present study estimates the contributions of various organic amendments to soil organic carbon (SOC). The present work discusses data from a 32-year fertilization experiment using vertisol soil. Five treatments with four field replications were included: no fertilizer (CK), mineral fertilizers only (NPK), wheat straw plus NPK (SNPK), swine manure plus NPK (PMNPK), and cattle manure plus NPK (CMNPK). The 13C signature of SOC was measured by δ 13C natural isotope technology, and the carbon functional compositions of organic amendments were determined by solid-state 13C nuclear magnetic resonance spectra. The average proportions of native and crop residues derived organic carbon under the SNPK, PMNPK and CMNPK treatments were 43, 40, 29, and 51, 51, 39%, respectively. The average proportions of organic carbon-derived from wheat straw (SNPK), swine and cattle manure (PMNPK and CMNPK) were 6, 9, and 32%, respectively. The quantitative relationship between carbon retention efficiency and fertilization year could be described by a significantly negative linear function (p < 0.05). The average organic carbon retention efficiencies for wheat straw, swine, and cattle manure differed substantially at 6, 10, and 31%, respectively. Their corresponding aromatic carbon contents were 6, 7, and 12%, respectively. Furthermore, incorporation of organic amendments, especially for cattle manure, led to a decrease in the yield variability and an increase in the sustainable yield index of crops compared with the CK and NPK treatments. In conclusion, the long-term continuous application of cattle manure is a preferred method for enhancing SOC storage and increasing crop production for vertisols. 相似文献
3.
Jinling Lv Xuejun Liu Hua Liu Xihe Wang Kaihui Li Changyan Tian Peter Christie 《Nutrient Cycling in Agroecosystems》2014,98(1):15-26
A long-term fertilizer experiment investigating cotton-based cropping systems established in 1990 in central Asia was used to quantify the emissions of CO2, CH4 and N2O from April 2012 to April 2013 to better understand greenhouse gas (GHG) emissions and net global warming potential (GWP) in extremely arid croplands. The study involved five treatments: no fertilizer application as a control (CK), balanced fertilizer NPK (NPK), fertilizer NPK plus straw (NPKS), fertilizer NPK plus organic manure (NPKM), and high rates of fertilizer NPK and organic manure (NPKM+). The net ecosystem carbon balance was estimated by the changes in topsoil (0–20 cm) organic carbon (SOC) density over the 22-year period 1990–2012. Manure and fertilizer combination treatments (NPKM and NPKM+) significantly increased CO2 and slightly increased N2O emissions during and outside the cotton growing seasons. Neither NPK nor NPKS treatment increased SOC in spite of relatively low CO2, CH4 and N2O fluxes. Treatments involving manure application showed the lowest net annual GWP and GHG intensity (GHGI). However, overuse of manure and fertilizers (NPKM+) did not significantly increase cotton yield (5.3 t ha?1) but the net annual GWP (?4,535 kg CO2_eqv. ha?1) and GHGI (?0.86 kg CO2_eqv. kg?1 grain yield of cotton) were significantly lower than in NPKM. NPKS and NPK slightly increased the net annual GWP compared with the control plots. Our study shows that a suitable rate of fertilizer NPK plus manure may be the optimum choice to increase soil carbon sequestration, maintain crop yields, and restrict net annual GWP and GHGI to relatively low levels in extremely arid regions. 相似文献
4.
Sheng-Mao Yang S. S. Malhi Jian-Rong Song You-Cai Xiong Wei-Yun Yue Li Li Lu Jian-Guo Wang Tian-Wen Guo 《Nutrient Cycling in Agroecosystems》2006,76(1):81-94
Application of chemical fertilizers and farmyard manure affects crop productivity and improves nutrient cycling within soil–plant systems, but the magnitude varies with soil-climatic conditions. A long-term (1982–2004) field experiment was conducted to investigate the effects of nitrogen (N), phosphorus (P), and potassium (K) fertilizers and farmyard swine manure (M) on seed and straw yield, protein concentration, and N uptake in the seed and straw of 19-year winter wheat (Triticum aestivum L.) and four-year oilseed (three-year canola, Brassica napus L. in 1987, 2000 and 2003; one-year flax, Linum usitatisimum L. in 1991), accumulation of nitrate-N (NO3-N) in the soil profile (0–210 cm), and N balance sheet on a Huangmian soil (calcaric cambisols, FAO) near Tianshui, Gansu, China. The two main plot treatments were without and with farmyard swine manure (M); sub-plot treatments were control (Ck), N, NP, and NPK.␣The average seed yield decreased in the order MNPK ≥ MNP > MN ≥ NPK ≥ NP > M > N > Ck. The average effect of manure and fertilizers on seed yield was in the order M > N > P > K. The seed yield increase was 20.5% for M, 17.8% for N, 14.2% for P, and 2.9 % for K treatment. Seed yield response to fertilizers was much greater for N and P than for K, and it was much greater for no manure than for manure treatment. The response of straw yield to fertilization treatments was usually similar to that of seed yield. The N fertilizer and manure significantly increased protein concentration and N uptake plant. From the standpoint of increasing crop yield and seed quality, MNPK was the best fertilization strategy. Annual applications of N fertilizer and manure for 23 successive years had a marked effect on NO3-N accumulation in the 0–210 cm soil profile. Accumulation of NO3-N in the deeper soil layers with application of N fertilizer and manure is regarded as a potential danger, because of pollution of the soil environment and of groundwater. Application of N fertilizer in combination with P and/or K fertilizers reduced residual soil NO3-N significantly compared with N fertilizer alone in both no manure and manure plots. The findings suggest that integrated and balanced application of N, P, and K fertilizers and␣manure at proper rates is important for protecting soil and groundwater from potential NO3-N pollution and for maintaining high crop productivity in the rainfed region of Northwestern China. 相似文献
5.
Chemical fertilizer pollution control using drip fertigation for conservation of water quality in Danjiangkou Reservoir 总被引:1,自引:0,他引:1
Ronghao Liu Yaohu Kang Chao Zhang Liang Pei Shuqin Wan Shufang Jiang Shiping Liu Zhiyuan Ren Yi Yang 《Nutrient Cycling in Agroecosystems》2014,98(3):295-307
The use of drip fertigation to reduce fertilizer pollution of the Danjiangkou Reservoir of China was explored. Specifically, a 4-year experiment was conducted to identify the optimum fertilizer rate for fertigation of a tea plantation. The treatments included five fertigation levels, 10 % (10 % NPK), 20 % (20 % NPK), 30 % (30 % NPK), 40 % (40 % NPK) and 50 % (50 % NPK) of the traditional fertilizer dose, and the traditional fertilizer dose under rain-fed conditions as a control (CK). Relative to CK, fertigation treatments decreased total nitrogen (TN), total phosphorus (TP) runoff loss (kg ha?1) and TN and TP concentrations (mg kg?1) in leaching water by 51.9–70.8, 51.7–67.5, 56.1–85.4, and 39.1–56.5 %, respectively. Total N, TP runoff loss and TN concentrations in leaching water generally increased with increasing fertilization rate among fertigation treatments; however, there was no significant difference in TP concentrations of leaching water. Yield increased with increasing rate of fertilization among fertigation treatments. The yields of the 30–50 % NPK treatments were similar (P > 0.05), but higher (P < 0.05) than those of the 10–20 % NPK treatments. There were no significant differences in yield among the 30 % NPK, 40 % NPK and CK treatments. The relative yields increased rapidly when the relative fertilizer rate was between 10 and 33 %; however, this increase slowed at fertilization rates above 33 %. Based on the yield and fertilizer pollution control, fertigation with 33 % of the traditional fertilizer dose should be considered for tea production in the water source area. 相似文献
6.
Fractions of organic carbon in soils under different crop rotations, cover crops and fertilization practices 总被引:2,自引:0,他引:2
We investigated the long-term effects (13–48 years) of crop rotations, cover crops and fertilization practices on soil organic carbon fractions. Two long-term experiments conducted on a clay loam soil in southeastern Norway were used. From the crop rotation experiment, two rotations, one with two years grain + four years grass and the second with grain alone (both for 6 years), were selected. Each rotation was divided into moderate fertilizer rate (30–40 kg N ha–1), normal fertilizer rate (80–120 kg N ha–1) and farmyard manure (FYM 60 Mg ha–1 + inorganic N at normal rate). Farmyard manure was applied only once in a 6-year rotation, while NPK was applied to every crop. The cover crop experiment with principal cereal crops consisted of three treatments: no cover, rye grass and clover as cover crops. Each cover crop was fertilized with 0 and 120 kg ha–1 N rates. Soil samples from both experiments were taken from 0–10 cm and 10–25 cm depths in the autumn of 2001. The classical extraction procedure with alkali and acid solution was used to separate humic acid (HA), fulvic acid (FA) and humin fractions, while H2O2 was used to separate black carbon (BC) from the humin fraction. The rotation of grain + grass showed a significantly higher soil organic carbon (SOC) compared with grain alone at both depths. Farmyard manure application resulted in significantly higher SOC than that of mineral fertilizer only. However, cover crops and N rates did not affect SOC significantly. Organic carbon content of FA, HA and humin fractions accounted for about 29%, 25% and 44% of SOC, respectively. The rotation of grain+grass gave a higher C content in HA and humin fractions, and a lower C in the FA fraction as compared with the rotation with grain alone. Farmyard manure increased HA and humin fractions more than did chemical fertilizers. Clover cover crop increased the C proportion of humin more than rye grass and no cover crop. No significant differences in C contents of FA, HA and humin fractions were observed between N rates. Effects of cover crop and N rates as well as fertilization with NPK on black carbon (BC) content were significant only at 10–25 cm depths. Farmyard manure increased the BC fraction compared with chemical fertilizers. Clover crop also enhanced the accumulation of the BC fraction. Application of 120 kg N ha–1 resulted in a significant increase of the BC fraction. 相似文献
7.
Long term effects of fertilization on carbon and nitrogen sequestration and aggregate associated carbon and nitrogen in the Indian sub-Himalayas 总被引:4,自引:0,他引:4
Ranjan Bhattacharyya Ved Prakash S. Kundu A. K. Srivastva H. S. Gupta S. Mitra 《Nutrient Cycling in Agroecosystems》2010,86(1):1-16
An understanding of the dynamics of soil organic carbon (SOC) as affected by farming practices is imperative for maintaining
soil productivity and also for restraining global warming by CO2 evolution. Results of a long-term (30 year) experiment in the Indian Himalayas under rainfed soybean (Glycine max L.)—wheat (Triticum aestivum L.) rotation was analyzed to determine the influence of mineral fertilizer and farmyard manure (FYM) application at 10 Mg ha−1 on SOC and total soil nitrogen (TSN) stocks and distribution within different aggregate size fractions. Fertilizers (NP,
NK and NPK) and FYM in combination with N or NPK were applied before the soybean crop every year and no nutrient was applied
before the wheat crop. Results showed that addition of FYM with N or NPK fertilizers increased SOC and TSN contents. The overall
gain in SOC in the 0- to 45-cm soil depth interval in the plots under NPK + FYM treatment over NPK was 17.18 Mg C ha−1 in 30 year. The rate of conversion of input C to SOC was about 19% of each additional Mg C input per hectare. SOC content
in large size aggregates was greater than in smaller size aggregates, and declined with decreased aggregate size. Thus, long-term
soybean–wheat rotation in a sandy loam soil of the Indian Himalayas sequestered carbon and nitrogen. Soil organic C and TSN
sequestration in the 0.25- to 0.1-mm size fraction is an ideal indicator of long-term C and N sequestration, since this fraction
retained maximum SOC/TSN stock. 相似文献
8.
In agro-ecosystems, the relationship between soil fertility and crop yield is mediated by manure application. In this study, an 8-year field experiment was performed with four fertilizer treatments (NPK, NPKM1, NPKM2, and NPKM3), where NPK refers to chemical fertilizer and M1, M2, and M3 refer to manure application rates of 15, 30, and 45 Mg ha?1 year?1, respectively. The results showed that the NPKM (NPKM1, NPKM2, and NPKM3) treatments produced greater and more stable yields (4.95–5.45 Mg ha?1 and 0.59–0.75) than the NPK treatment (4.01 Mg ha?1 and 0.50). Crop yields under the NPKM treatments showed two trends, with a rate of decrease of 0.48–0.83 Mg ha?1 year?1 during the first 4 years and a rate of increase of 0.10–0.25 Mg ha?1 year?1 during the last 4 years. The soil organic carbon (SOC) significantly increased under all treatments. The estimated annual SOC decomposition rate was 0.35 Mg ha?1 year?1 and the equilibrium SOC level was 6.22 Mg ha?1. Soil total nitrogen (N), available N, total phosphorus (P) and available P under the NPKM treatments increased by 0.15–0.26, 15–33, 0.17–0.66 and 45–159 g kg?1, respectively, compared with the NPK treatment. Manure application mainly influenced crop yield by affecting the soil TN, available N, and available P, which accounted for up to 64% of the crop yield variation. Taken together, applying manure can determine or at least improve the effects of soil fertility on crop yield in acidic soils in South China. 相似文献
9.
Evaluation of current fertilizer practice and soil fertility in vegetable production in the Beijing region 总被引:21,自引:0,他引:21
Qing Chen Xiaosheng Zhang Hongyan Zhang Peter Christie Xiaolin Li Dieter Horlacher Hans-Peter Liebig 《Nutrient Cycling in Agroecosystems》2004,69(1):51-58
A survey on current fertilizer practices and their effects on soil fertility and soil salinity was conducted from 1996 to 2000 in Beijing Province, a major vegetable production area in the North China Plain. Inputs of the major nutrients (NPK) and fertilizer application methods and sources for different vegetable species and field conditions were evaluated. Excessive N and P fertilizer application, often up to about 5 times the crop requirement in the case of N, was very common, especially for high-value crops. Potassium supply may have been inadequate for some crops such as leafy vegetables. Urea, diammonium orthophosphate ((NH4)2HPO4) and chicken manure were the major nutrient sources for vegetable production in the region. Over 50% of N, 60% of P and nearly 90% of K applied originated from organic manure. Total N application rate for open-field Chinese cabbage from organic manure and inorganic fertilizers ranged from 300 to 900 kg N ha–1 on 78% of the farms surveyed. More than 35% of the surveyed greenhouse-grown tomato crops received > 1000 kg N ha–1 from organic and inorganic sources. A negative K balance (applied K minus K removed by the crop) was found in two-thirds of the surveyed fields of open-field Chinese cabbage and half of the surveyed fields of greenhouse-grown tomato. Plant-available N, P and K increased with increasing length of the period the greenhouse soils had been used for vegetable production. Similarly, soil salinity increased more in greenhouse soils than in open-field soils. The results indicate that balanced NPK fertilizer use and maintenance of soil quality are important for the development of sustainable vegetable production systems in this region. 相似文献
10.
11.
The effects of 18 years continuous cropping of irrigated rice on soil and yields were studied in two long-term fertility experiments
(LTFE) at Ndiaye and Fanaye in the Senegal River Valley (West Africa). Rice was planted twice in a year during the hot dry
season (HDS) and wet season (WS) with different fertilizer treatments. Soil organic carbon (SOC) under fallow varied from
7.1 g kg−1 at Fanaye to 11.0 g kg−1 at Ndiaye. Rice cropping maintained and increased SOC at Ndiaye and Fanaye, respectively and fertilizer treatments did not
affect SOC. Soil available P and exchangeable K were maintained or increased with long-term application of NPK fertilizers.
Without any fertilizer, yields decreased by 60 kg ha−1 (1.5%) and 115 kg ha−1 (3%) per year at Fanaye and Ndiaye, respectively. The highest annual yield decreases of 268 kg ha−1 (3.6%) and 277 kg ha−1 (4.1%) were observed at Fanaye and Ndiaye, respectively when only N fertilizer was applied. Rice yields were only maintained
with NPK fertilizers supplying at least 60 kg N, 26 kg P and 50 kg K ha−1. It was concluded that the double cropping of irrigated rice does not decrease SOC and the application of the recommended
doses of NPK fertilizer maintained rice yields for 18 years. 相似文献
12.
Nitrogen Cycling with Respect to Environmental Load in Farm Systems
in Southwest China 总被引:2,自引:0,他引:2
In Qibainong, a steep-mountainous karst region in southwestern China, self-sustaining societies have long existed, but increasing
socioeconomic liberation has fuelled the recent rapid structural change of its economy. Consequently, environmental deterioration
and exhaustion of resources have become problematic issues. We carried out a field survey in Qibainong in southwestern China
and used both estimated and measured N flows and N balances from obtained results. Our results are summarized as follows (1)
farmers used large amounts of chemical N fertilizers at intensities of 113–1124 kg N ha−1; (2) substantial application of chemical fertilizer in Qibainong has contributed to an increase in potential NO3-N leaching of 6–511 kg N ha−1, followed by NH3 volatilization; (3) crop products are largely distributed to feed livestock, the products of which are a major income source;
(4) this area has a great requirement for imported food; (5) in addition, unused manure N (up to 191 kg N ha−1) is generated by the increase in manure N production. Chemical fertilizer application, in addition to unused manure can be
regarded as a major source of environmental damage. Based on the relationship between the N application rate and the NO3-N leaching potential, we estimated the critical limit of the N application rate of chemical fertilizer + manure to be 297 kg
N ha−1. In Qibainong, unused manure, which is an important nutrient resource, was applicable within the critical limit. We recommend
that all manure N produced within the village be used effectively on arable land, and that any shortages be supplemented by
chemical N fertilizer up to 297 kg N ha−1 to maintain water resource quality. Further improvement might be achieved through incorporating chemical fertilizers, P and
K supplemented manure, and so on. 相似文献
13.
Reducing interflow nitrogen loss from hillslope cropland in a purple soil hilly region in southwestern China 总被引:4,自引:0,他引:4
Interflow related nitrogen (N) loss from hillslope cropland is a global issue of concern. Field experiments were carried out in purple soil to study how to reduce interflow related N loss by substituting organic fertilizers for mineral fertilizers. Study conditions were engineered where identical amounts of N were applied to four different fertilization regimes: N fertilizer only, mineral fertilizers (MF), mineral fertilizers with livestock manure (MFL), and mineral fertilizers with crop straw (MFS). Results showed that total MFL and MFS interflow N loss decreased by 44.1 and 36.9?%, respectively, compared to the MF fertilization regime, using identical amounts of N. Furthermore, crop yields for the MFL and MFS fertilization regimes were higher compared to the MF fertilization regime. These findings can result in an important new means in controlling interflow N loss from hillslope cropland by substituting organic fertilizers for a port of mineral fertilizers, using identical amounts of organic fertilizer. 相似文献
14.
Soil organic carbon,total nitrogen and grain yields under long-term fertilizations in the upland red soil of southern China 总被引:13,自引:0,他引:13
A long-term experiment with various fertilizations was carried out during 1990–2006 in a double cropping system rotated with
wheat (Triticum Aestivium L.) and corn (Zea mays L.) in the red soil of southern China. The experiment consisted of eight treatments: non-fertilization (CK), nitrogen–phosphorus
fertilization (NP), phosphorus–potassium fertilization (PK), nitrogen–phosphorus–potassium fertilization (NPK), pig manure
(M), pig manure and NPK fertilization (NPKM), high rates of NPKM (hNPKM), and straw returned with inorganic fertilizers (NPKS).
Applications of manure (i.e., M, NPKM and hNPKM) significantly increased soil organic carbon (SOC) and total nitrogen contents.
Applications of inorganic fertilizers without manure showed small influences on SOC, but resulted in declines of soil total
nitrogen over the long-term experiment. Grain yields were more than doubled under fertilizations for both wheat and corn,
with the highest under the NPKM and hNPKM treatments and the lowest under non-fertilization. Long-term cropping practices
without fertilization or with unbalanced fertilizations (e.g., NP and PK) caused low grain yields. The balanced fertilization
of NPK increased grain yields. However, such practice was not able to maintain high grain yields during the last few years
of experiment. Our analyses indicate that both wheat and corn grain yields are significantly correlated with SOC, total and
available nitrogen and phosphorus. However, the relationships are stronger with total nitrogen (r = 0.5–0.6) than with available nitrogen (r = 0.26–0.3), indicating the importance of maintaining soil total nitrogen in agricultural practice. 相似文献
15.
C.J. Pilbeam P.J. Gregory R.C. Munankarmy B.P. Tripathi 《Nutrient Cycling in Agroecosystems》2004,69(3):221-232
Intensification of crop production in the mid-hills of Nepal has led to concerns that nitrogen loss by leaching may increase. This study estimated the amount of N leached during two years from rainfed terraces (bari-land) at three locations in Nepal. Maize or upland rice grown in the monsoon season was given either no nutrient inputs or inputs via either nitrogen fertilizer or farmyard manure. Nitrate concentration in soil solution was measured regularly with porous ceramic cup samplers and drainage estimated from a simple soil water balance. Estimated losses of nitrogen by leaching ranged from 0 to 63.5 kg N ha–1 depending on location and the form of nitrogen applied. Losses from plots receiving no nutrient inputs were generally small (range: 0–35 kg N ha–1) and losses from plots where nitrogen was applied as manure (range: 2–41 kg N ha–1) were typically half those from plots with nitrogen applied as fertilizer. Losses during the post-monsoon crops of finger millet were small (typically <5% of total loss) although losses from the one site with blackgram were larger (about 13%). The highest concentrations of nitrate in solution were measured early in the season as the monsoon rains began and immediately following fertilizer applications. Leaching losses are likely to be minimised if manure is applied as a basal nutrient dressing followed by fertilizer nitrogen later in the season. 相似文献
16.
Ranjan Bhattacharyya S. C. Pandey S. Chandra S. Kundu Supradip Saha B. L. Mina A. K. Srivastva H. S. Gupta 《Nutrient Cycling in Agroecosystems》2010,86(2):255-268
To date, the sustainability of wheat (Triticum
aestivum)–soybean (Glycine
max) cropping systems has not been well assessed, especially under Indian Himalayas. Research was conducted in 1995–1996 to 2004
at Hawalbagh, India to study the effects of fertilization on yield sustainability of irrigated wheat–soybean system and on
selected soil properties. The mean wheat yield under NPK + FYM (farmyard manure) treated plots was ~27% higher than NPK (2.4 Mg ha−1). The residual effect of NPK + FYM caused ~14% increase in soybean yield over NPK (2.18 Mg ha−1). Sustainable yield index values of wheat and the wheat–soybean system were greater with annual fertilizer N or NPK plots
10 Mg ha−1 FYM than NPK alone. However, benefit:cost ratio of fertilization, agronomic efficiency and partial factor productivity of
applied nutrients were higher with NPK + FYM than NPK, if FYM nutrients were not considered. Soils under NPK + FYM contained
higher soil organic C (SOC), total soil N, total P and Olsen-P by ~10, 42, 52 and 71%, respectively, in the 0–30 cm soil layers,
compared with NPK. Non-exchangeable K decreased with time under all treatments except NPK. Total SOC in the 0–30 cm soil layer
increased in all fertilized plots. Application of NPK + FYM also improved selected soil physical properties over NPK. The
NPK + FYM application had better soil productivity than NPK but was not as economical as NPK if farmers had to purchase manure. 相似文献
17.
Krishna R. Tiwari Bishal K. Sitaula Roshan M. Bajracharya Trond Børresen 《Nutrient Cycling in Agroecosystems》2010,86(2):241-253
On-farm runoff plots were established during 2004 and monitored for 4 years in the Pokhare Khola watershed (Nepal) in a completely
randomized design with four replications of each three treatments: traditional Farmer Practice (FP) (Zea mays–Eleusine coracana), Reduced Tillage (RT; Z. mays–Vigna ungeuculata), and Commercial Vegetable with double dose of farm yard manure (CV; Z. mays–Capsicum species) to evaluate treatment effects on soil nutrient losses, nutrient balances and crop income on Bari land (rainfed terraces). Nutrient removal due to crop harvest was found to be significantly higher than nutrient loss through
soil erosion, and CV treatment exhibited a significantly higher N uptake (123 kg ha−1 year−1) through crop harvest than other treatments. Moreover, the CV treatment produced significantly higher income per unit area
of Bari land than the other treatments. Soil organic carbon and major nutrients losses (NPK) through soil erosion were minimal [25.5 kg ha−1 year−1 soil organic carbon (SOC) and 5.6:0.02:0.12 kg ha−1 year−1 nitrogen (N), phosphorus (P), potassium (K), respectively]. Result showed that no nutrients were lost through leaching. Nutrient
losses due to soil erosion and runoff were lower than previously reported in the Middle Mountain region, indicating a need
to re-evaluate the soil erosion and nutrient loss problems in this region. Interventions such as reduced tillage and double
dose of FYM with vegetable production were found to be effective in maintaining soil fertility and increasing farm income
compared to the traditional maize-millet production system. The nutrient balance calculations suggest that integrated nutrient
management techniques such as residue incorporation and application of FYM with a minimum application of chemical fertilizer
are potentially sustainable production approaches for the Mid-hills of Nepal. 相似文献
18.
Soybean-maize rotation is a profitable cropping system and is used under rain fed conditions in north China. Since crop yields
have been reported to decrease when K fertilizers are not used, we analyzed the productivity trends, soil-exchangeable and
non-exchangeable K contents, and K balance in a continuous cropping experiment conducted in an area with an alfisol soil in
the Liaohe River plain, China. The trial, established in early 1990 and continued till 2007, included 8 combinations of recycled
manure and N, P, and K fertilizers. In the unfertilized plot, the yields of soybean and maize were 1,486 and 4,124 kg ha−1 respectively (mean yield over 18 years). The yields of both soybean and maize increased to 2,195 and 7,476 kg ha−1, respectively, in response to the application of inorganic N, P, and K fertilizers. The maximum yields of soybean (2,424 kg ha−1) and maize (7,790 kg ha−1) were obtained in the plots under treatment with N, P, and K fertilizers and recycled manure. K was one of the yield-limiting
macronutrients: regular K application was required to make investments in the application of other mineral nutrients profitable.
The decrease in the yields of soybean and maize owing to the absence of K application averaged 400 and 780 kg ha−1, respectively. Soybean seed and maize grain yields significantly increased with the application of recycled manure. For both
these crops, the variation coefficients of grain were lower with treatments that included recycled manure than without treatment.
After 18 years, the soil-exchangeable and non-exchangeable K concentrations decreased; the concentrations in the case of treatments
that did not include K fertilizers were not significantly different. Treatment with N, P, and K fertilizers appreciably improved
the fertility level of the soil, increased the concentration of soil-exchangeable K, and decreased the non-exchangeable K
concentration. In soils under treatment with N, P, and K fertilizers and recycled manure, the soil-exchangeable and non-exchangeable
K levels in the 0–20 cm-deep soil layer increased by 34% and 2%, respectively, over the initial levels. Both soil-exchangeable
and non-exchangeable K concentrations were the highest with on treatment with N, P, and K fertilizers and recycled manure,
followed by treatment with N, P, and K fertilizers. These concentrations were lowest in unfertilized soils; the other treatments
yielded intermediate results. The results showed a total removal of K by the crops, and the amount removed exceeded the amount
of K added to the soil; in treatments that did not include K fertilizers, a net negative K balance was observed, from 184
to 575 kg ha−2. The combined use of N, P, and K fertilizers and recycled manure increased the K content of the 0–20 cm-deep soil layer by
125% compared to the increase obtained with the application of N, P, and K fertilizers alone. The results clearly reveal that
current mineral fertilizer applications are inadequate; instead, the annual application of recycled manure along with N, P,
and K fertilizers could sustain future yields and soil productivity. 相似文献
19.
Soil organic matter (SOM), besides influencing carbon (C) transfer between soils and atmosphere, impacts soil functional ability
and its response to environmental and anthropogenic influences. We studied the impact of continuous application of rice straw
and farmyard manure (FYM) either alone or in conjunction with inorganic fertilizers on aggregate stability and distribution
of C and nitrogen (N) in different aggregate fractions after 7 years of rice–wheat cropping on a sandy loam soil. Macroaggregates
(>0.25 mm) constituted 32.5–54.5% of total water stable aggregates (WSA) and were linearly related (R
2 = 0.69) to soil organic carbon content. The addition of rice straw and FYM significantly (P < 0.05) improved the formation of macroaggregates with a concomitant decrease in the proportion of microaggregates at all
the three sampling depths (0–5, 5–10 and 10–15 cm). Macroaggregates had higher C and N density as compared to microaggregates.
Application of rice straw and FYM improved C and N density in different aggregate sizes and the improvement was greatest in
plots that received both rice straw and FYM each year. Application of FYM along with inorganic fertilizer resulted in a net
C sequestration of 0.44 t ha−1 in the plough layer after 7 years of rice–wheat cropping. Carbon sequestration was greater (1.53 t ha−1) when both rice straw and FYM along with inorganic fertilizers were applied annually. It is concluded that addition of rice
straw and FYM in rice–wheat system improves soil aggregation and enhances C and N sequestration in macroaggregates. This will
help in sustainable rice–wheat productivity in the region. 相似文献
20.
Leaching losses of nitrate nitrogen and dissolved organic nitrogen from a yearly two crops system,wheat-maize,under monsoon situations 总被引:6,自引:0,他引:6
Manxiang Huang Tao Liang Zhu Ou-Yang Lingqing Wang Chaosheng Zhang Chenghu Zhou 《Nutrient Cycling in Agroecosystems》2011,91(1):77-89
A large amount of nitrogen (N) fertilizers applied to the winter wheat–summer maize double cropping systems in the North China
Plain (NCP) contributes largely to N leaching to the groundwater. A series of field experiments were carried out during October
2004 and September 2007 in a lysimeter field to reveal the temporal changes of N leaching losses below 2-m depth from this
land system as well as the effects of N fertilizer application rates on N leaching. Four N rates (0, 180, 260, and 360 kg N ha−1 as urea) were applied in the study area. Seasonal leachate volumes were 87 and 72 mm in the first and second maize season,
respectively, and 13 and 4 mm during the winter wheat and maize season in the third rotational year, respectively. The average
seasonal flow-weighted NO3-N concentrations in leachate for the four N fertilizer application rates ranged from 8.1 to 103.7 mg N l−1, and seasonal flow-weighted dissolved organic nitrogen (DON) concentrations in leachate varied from 0.8 to 6.0 mg N l−1. Total amounts of NO3-N leaching lost throughout the 3 years were in the range of 14.6 to 177.8 kg ha−1 for the four N application rates, corresponding to N leaching losses in the range of 4.0–7.6% of the fertilizers applied.
DON losses throughout the 3 years were 1.4, 2.1, 3.6, and 6.3 kg N ha−1 for the four corresponding fertilization rates. The application rate of 180 kg N ha−1 was recommended based on the balance between reducing N leaching and maintaining crop yields. The results indicated that
there is a potential risk of N leaching during the winter wheat season, and over-fertilization of chemical N can result in
substantial N leaching losses by high-intensity rainfalls in summer. 相似文献