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1.
S. Sitthaphanit V. Limpinuntana B. Toomsan S. Panchaban R. W. Bell 《Nutrient Cycling in Agroecosystems》2009,85(2):123-139
Fertiliser application strategies for maize (Zea
mays L.) production on sandy soils under high rainfall regimes need to be carefully designed to minimise nutrient losses through
leaching and maximise crop yield. Experiments were conducted to determine N, P, and K leaching in sandy soils with 3–6% clay
in surface layers under maize production, and the effectiveness of different N, P, and K fertiliser timing and splitting strategies
on leaching of N, P, and K and on maize yield. In a column experiment on an Oxic Paleustult (Korat series) with 3% clay, leaching
of N, P, and K from fertiliser (114N-17P-22K in kg ha−1) was significant under simulated rainfall, but decreased to negligible levels with 3–5 split applications of fertiliser.
Maize N and K uptake increased with 3–5 split applications, but not P uptake. Despite continued intense rainfall and further
fertilizer additions, leaching was not recorded after day 30, and this was attributed to the effect of plant water uptake
on reducing deep drainage. Split applications of fertilizer maintained NP and K in the 0–30 cm layer during 30–60 days when
maize nutrient demand was likely to be at its highest, while in the recommended fertilizer regime NPK in the surface layers
declined after 30 days. In a field experiment on an Oxic Paleustult (Korat series) with 6% clay, 3–4 splits of fertiliser
increased N and K uptake and increased maize yields from 3.3 to 4.5 Mg ha−1. Postponing basal fertiliser application from pre-planting to 7–15 days after emergence increased uptake of N, P, and K and
grain yield emphasising the greater risk of nutrient losses from fertiliser applied at planting than later. Strategies designed
to reduce the amount of nutrients applied as fertiliser at planting, such as split application and postponing basal application
can decrease the risk of leaching of N, P, and K from fertiliser and improve nutrient use efficiency, and grain yield of maize
on sandy soils under high growing season rainfall regimes. 相似文献
2.
Intensively grazed, rain-fed dairy pastures on the predominantly sandy soils in the high rainfall (>800 mm annual average)
Mediterranean-type climate of south-western Australia comprise >90% ryegrass (annual ryegrass, Lolium rigidum Gaud. and Italian ryegrass, L. multiflorum Lam.). To maximise pasture use for milk production, the pastures are rotationally grazed by starting grazing when ryegrass
plants have 3 leaves per tiller, and fertiliser nitrogen (N) and sulfur (S), in the ratio of 3–4 N and 1S, need to be applied
after each grazing for profitable pasture dry matter (DM) production. In addition, farmers usually also apply low levels of
phosphorus (P) and potassium (K) fertiliser to these pastures after each grazing, despite Colwell soil test P usually being
well above critical values for pasture production, and fertilizer K being only required for clover in the traditional clover
(Trifolium subterraneum L.) ryegrass pastures of the region. In field experiments undertaken May 2006–June 2010 on intensively grazed ryegrass dairy
pastures in the region, no significant ryegrass DM responses to applied fertiliser P or K were obtained, regardless of level
or method of P or K application. When no P was applied, soil test P declined gradually, by between 4.4 and 7.1 mg/kg per year,
and remained above the critical value for the soils at 2 sites, but declined below the critical value for soil at a third
site. Critical soil test P is located near the maximum yield plateau in the flat part of the relationship between yield and
soil test P, particularly when, as appropriate for dairy production, the critical value is for 95% of the maximum pasture
DM yield. Consequently, when no P is applied and soil test P decreases, significant pasture DM yield decreases will only occur
when soil test P approaches the steeper part of the relationship, which can take some time. In addition, as occurs on farms,
faeces deposited by cows while grazing supplied P to pasture even when no fertiliser P was applied. Soil K testing proved
unreliable for indicating the need for fertiliser K applications to pasture in the next growing season because many soil samples
collected within and between urine patches contained elevated levels of K deposited by cows while grazing. We conclude fertiliser
P should only be applied to intensively grazed ryegrass dairy pastures when soil testing indicates it is required. Further
research is required to assess if plant K testing is an alternative, but urine patches may also pose a problem for plant testing. 相似文献
3.
Crop productivity and nutrient use efficiency as affected by long-term fertilisation in North China Plain 总被引:3,自引:0,他引:3
Yingchun Wang Enli Wang Daolong Wang Shaomin Huang Yibing Ma Chris J. Smith Ligang Wang 《Nutrient Cycling in Agroecosystems》2010,86(1):105-119
Nutrient inputs into crop production systems through fertilisation have come under increased scrutiny in recent years because
of reduced nutrient use efficiency and increased environmental impact. Fifteen years of experimental data on dynamics of N,
P and K in soil, crop yield and nutrient uptake from nine fertilisation treatments at Zhengzhou, North China Plain, were used
to analyse the contribution of different fertilisation treatments to crop yield, nutrient use efficiency and accumulation
of nutrients in soil. The results showed that both N and P were limiting factors for crop growth. Without additional N and
P fertilisation, only a very low yield level (ca 2 t ha−1 for wheat and 3 t ha−1 for maize) could be maintained. To achieve the potential productivity (i.e. yield level free of water and nutrient stresses)
of wheat (6.9 t ha−1) and maize (8.3 t ha−1), wheat would need, on average, 170 kg N ha−1, 32 kg P ha−1 and 130 kg K ha−1, while maize would need 189 kg N ha−1, 34 kg P ha−1 and 212 kg K ha−1. The N and P demands correspond well to the N and P levels supplied in one of the fertilisation treatments (NPK), while K
deficiency could occur in the future if no crop residues were returned or no extra K was applied. On average under this NPK
treatment, 80% of N and 71% of P could be recovered by the wheat–maize system. Treatments with nutrient inputs higher than
the NPK treatment and treatments without combination of N and P have led to accumulation of N and P in the soil profile. The
input levels of N and P in the NPK treatment are recommended in fertiliser management, with additional K to avoid future soil
K deficiency. 相似文献
4.
Chun Song Enli Wang Xiaozeng Han Richard Stirzaker 《Nutrient Cycling in Agroecosystems》2011,89(3):363-374
A 19-year field experiment on a Mollisol agroecosystem was carried out to study the productivity of a wheat-maize-soybean
rotation and the changes in soil carbon and nutrient status in response to different fertiliser applications in Northeast
China. The experiment consisted of seven fertiliser treatments: (1) unfertilised control, (2) annual application of P and
K fertilisers, (3) N and K fertilisers, (4) N and P fertilisers, (5) N, P and K fertilisers, (6) N, K and second level P fertilisers,
and (7) N, P and second level K fertilisers. Without fertiliser, the Mollisols could support an average yield of 1.88 t ha−1 for wheat, 3.89 t ha−1 for maize and 2.12 t ha−1 for soybean, compared to yields of 3.20, 9.30 and 2.45 t ha−1 respectively for wheat, maize and soybean if the crop nutrient demands were met. At the potential yield level, the N, P and
K removal by wheat are 79 kg N ha−1, 15 kg P ha−1, and 53 kg K ha−1, by maize are 207 kg N ha−1, 47 kg P ha−1, and 180 kg K ha−1, by soybean are 174 kg N ha−1, 18 kg P ha−1, and 55 kg K ha−1. Crop yield, change in soil organic carbon (SOC), and the total and available nutrient status were used to evaluate the fertility
of this soil over different time periods. This study showed that a fertiliser strategy that was able to maintain yields in
the short term (19 years) would not maintain the long term fertility of these soils. Although organic carbon levels did not
rise to the level of virgin soil in any treatment, a combination of N, P and K fertiliser that approximated crop export was
required to stabilise SOC and prevent a decline in the total store of soil nutrients. 相似文献
5.
Margarida Arrobas Maria João Parada Paula Magalhães M. Ângelo Rodrigues 《Nutrient Cycling in Agroecosystems》2011,89(3):329-339
The effect of three fertilisers that delay the bioavailability of nitrogen (N) in the soil was compared with ammonium nitrate
and a zero N control in two irrigated turfs in NE Portugal. The fertilisers used were: Floranid permanent 16-7-15 (slow-release,
IBDU/Isodur fertiliser); Basacote plus 9M 16-8-12 (controlled-release fertiliser, copolymer ethylene acrylic); Nitroteck 20-8-10
(stabilized fertiliser, dicyandiamide as nitrification inhibitor + coating with polyterpene) and Nitrolusal (ammonium nitrate,
20.5% N), applied all at a rate of 120 kg N ha−1. Nitrolusal was split into two fractions of 60 kg N ha−1. Phosphorus (P) and potassium (K) rates were balanced among treatments by using superphosphate (18% P2O5) and potassium chloride (60% K2O). The turf dry matter (DM) yield and N concentration in dry material were determined from several cuts of biomass throughout
the growing season. Based on DM yield, N concentration in dry material and fertilisation costs, indices of N use efficiency
and economic efficiency were estimated. Soil nitrate levels were monitored by using anion exchange membranes inserted directly
into the soil. Basacote gave significantly lower DM yields than the other fertilised treatments. The apparent N recovery of
Basacote was also the lowest. The results showed that Basacote released less N than that required for an adequate plant growth
in the beginning of the growing season, hampered the flush of spring growth. Furthermore, the release period of this Basacote
formulation, in the environmental conditions of these experiments, seemed to be longer than the length of the growing season.
Nitroteck and Floranid yielded similar or even higher DM and apparent N recovery values than did Nitrolusal. The indices of
economic efficiency ordered the fertilisers as Nitroteck > Nitrolusal > Floranid > Basacote or Nitrolusal > Nitroteck > Floranid > Basacote,
if the costs of P and K fertilisers used to balance the P and K rates in the experimental design were, respectively, taken
or not taken into account. 相似文献
6.
Michael J. Webb 《Nutrient Cycling in Agroecosystems》2009,83(2):163-178
The theory, and the statistics and mathematics of using factorial fertiliser trials to assist in making fertiliser recommendations
for neighbouring commercial plantings is presented as a conceptual framework and in a format for practical application. As
an example, the yield and leaf nutrient levels from a typical factorial fertiliser rate trial (nitrogen by potassium) were
modelled using multiple linear regression and the resulting response surfaces used to determine the maximum agronomic yield
and optimum economic yield and to calculate the requirement for ‘basal’ fertiliser. Leaf nutrient data in both the trial and
commercial plantings was used to estimate the requirement for ‘corrective’ fertiliser, where necessary, to increase the leaf
nutrient levels to the target leaf nutrient level for maximum yield. All the mathematics required can be incorporated into
a spreadsheet calculator that uses costs (e.g. fertiliser) and prices (e.g. oil) to calculate optimum economic fertiliser
application rates. Problems with extrapolating the results of fertiliser trials to commercial plantings can be overcome by
matching each trial with a corresponding commercial planting domain. 相似文献
7.
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
8.
Agronomic and economic evaluation of site-specific nutrient management for irrigated wheat in northwest India 总被引:1,自引:0,他引:1
Harmandeep S. Khurana Steven B. Phillips Bijay-Singh Marcus M. Alley Achim Dobermann Ajmer S. Sidhu Yadvinder-Singh Shaobing Peng 《Nutrient Cycling in Agroecosystems》2008,82(1):15-31
Similar to other regions of Asia, irrigated wheat (Triticum aestivum L.) yield increases in Punjab, India, have slowed in recent years. Future yield increases may occur in smaller increments
through fine-tuning of crop management mainly by accounting for the large spatial and temporal variation in soil characteristics.
On-farm experiments were conducted from 2002–03 to 2004–05 on 56 irrigated wheat farms (hereafter referred to as ‘sites’)
in six key irrigated rice (Oryza sativa L.)-wheat regions of Punjab to evaluate an approach for site-specific nutrient management (SSNM). Site-specific N–P–K applications
were calculated by accounting for the indigenous nutrient supply, yield targets, and nutrient demand as a function of the
interactions between N, P, and K. The performance of SSNM was tested for two wheat crops. Compared with the current farmers’
fertilizer practice (FFP), average grain yield increased from 4.2 to 4.8 Mg ha−1, while plant N, P, and K accumulations increased by 12–20% with SSNM. The gross return above fertilizer cost (GRF) was about
13% greater with SSNM than with FFP. Improved timing and/or splitting of fertilizer N increased N recovery efficiency from
0.17 kg kg−1 in FFP plots to 0.27 kg kg−1 in SSNM plots. The agronomic N use efficiency was 63% greater with SSNM than with FFP. As defined in our study, SSNM has
potential for improving yields and nutrient use efficiency in irrigated wheat. Future research must build on the present approach
to develop a more practical way for achieving similar benefits across large areas without site-specific modeling and with
minimum crop monitoring. 相似文献
9.
Bean (Phaseolus vulgaris L.) is important in sub-Saharan Africa for human dietary protein. Low yields are attributed to biotic and abiotic constraints including inadequate nutrient availability. Research was conducted to determine nutrient response functions for bean production areas of Kenya, Mozambique, Rwanda, Tanzania, and Zambia. Mean trial yields ranged from 0.32 to 2.60 and 1.72 to 2.89 Mg ha?1 for bush and climbing bean, respectively. Response to N was common except in Kenya and Mozambique. The main effect of P and K increased yield in Rwanda only but P and K effects were inconsistent in Zambia. Mean yield increase with a diagnostic treatment containing Mg–S–Zn–B was 0.41 and 0.58 Mg ha?1 for bush and climbing bean, respectively, in Rwanda and 0.36 Mg ha?1 in Tanzania with no effects in other countries. In Rwanda, the economically optimal rates (EOR) of N, P and K were > 20 kg ha?1, but higher with less costly fertilizer. Variations in EOR for growth type varied with nutrient. The EOR of N in Tanzania and Zambia were generally < 10 kg ha?1, depending on fertilizer costs, but P and K application had profit potential only in Rwanda. Yield, agronomic efficiency and profit to cost ratio, averaged across nutrients, were 36% less, 54% greater and 96% greater, respectively, with nutrients applied at 50% compared with 100% of EOR. Profit potential for the EOR of N is high when expected yield is > 1.5 Mg ha?1 but responses to P, K and Mg–S–Zn–B vary with bean production area. 相似文献
10.
Crop and soil nitrogen responses to phosphorus and potassium fertilization and drip irrigation under processing tomato 总被引:1,自引:0,他引:1
K. Liu T. Q. Zhang C. S. Tan T. Astatkie G. W. Price 《Nutrient Cycling in Agroecosystems》2012,93(2):151-162
Shortage of water or nutrient supplies can restrict the high nitrogen (N) demand of processing tomato, leaving high residual soil N resulting in negative environmental impacts. A 4-year field experiment, 2006?C2009, was conducted to study the effects of water management consisting of drip irrigation (DI) and non-irrigation (NI), fertilizer phosphorus (P) rates (0, 30, 60, and 90?kg P?ha?1), and fertilizer potassium (K) rates (0, 200, 400, and 600?kg?K?ha?1) on soil and plant N when a recommended N rate of 270?kg?N?ha?1 was applied. Compared with the NI treatment, DI increased fruit N removal by 101?%, plant total N uptake by 26?%, and N harvest index by 55?%. Consequently, DI decreased apparent field N balance (fertiliser N input minus plant total N uptake) by 28?% and cumulative post-harvest soil N in the 0?C100?cm depth by 33?%. Post-harvest soil N concentration was not affected by water management in the 0?C20?cm depth, but was significantly higher in the NI treatment in the 20?C100?cm depth. Fertilizer P input had no effects on all variables except for decreasing N concentration in the stems and leaves. Fertilizer K rates significantly affected plant N utilization, with highest fruit N removal and plant total N uptake at the 200?kg?K?ha?1 treatment; therefore, supplementing K had the potential to decrease gross N losses during tomato growing seasons. Based on the measured apparent field N balance and spatial distribution of soil N, gross N losses during the growing season were more severe than expected in a region that is highly susceptible to post-harvest soil N losses. 相似文献
11.
Ian J. Rochester 《Nutrient Cycling in Agroecosystems》2011,90(1):147-156
Improving the efficiency of nitrogen (N) fertiliser use is one means of reducing greenhouse gas emissions, particularly in
irrigated crops such as cotton (Gossypium hirsutum L.). Internal crop N use efficiency (iNUE) was measured within two N fertiliser rate experiments that covered a wide range of N fertility over six cropping seasons.
Crop iNUE was determined by dividing lint yield by crop N uptake. No nutrients other than N limited cotton growth or yield and the
crops were irrigated to avoid drought stress. The optimal N fertiliser rates were determined from fitted quadratic functions
that related lint yields with N fertiliser rates for each cropping system in each year. When the optimal N fertiliser rate
was applied, crop iNUE averaged 12.5 ± 0.2 kg lint/kg crop N uptake. The crop iNUE was then used to determine the degree to which N fertiliser was under or over-applied, with respect to the economic optimum
N fertiliser rate. Low iNUE values were associated with excessive N fertiliser application. Crop iNUE was determined in 82 commercial cotton crops in six valleys over the final 4 years of this study. The crop iNUE value was high in 8 fields (10%), optimal in 9 fields (11%) and low in 65 fields (79%). Crop N uptake averaged 247 kg N/ha,
yield 2,273 kg lint/ha and crop iNUE 10.1 kg lint/kg crop N uptake for these sites. Averaged over all sites and years, about 49 kg N/ha too much N fertiliser
was applied. Apparent N fertiliser recovery by cotton in the N rate experiments ranged from <20% in N-fertile treatments where
legume crops had been grown, to more than 60% following winter cereal crops. Information on crop iNUE will enable cotton producers to assess their N fertiliser management and adjust N fertiliser rates for future crops. This
study has demonstrated that there is scope to substantially reduce N fertiliser inputs to Australian cotton fields without
reducing yields. 相似文献
12.
Different fields within a farm have been observed to have different soil fertility status and this may affect the response
of a maize crop to applied N, P, and K fertiliser. A limiting nutrient trial was carried out at six farms each, in three districts
of Western Kenya. In each of the farms, the following treatments were laid out in three fields with different soil fertility
status at different distances from the homestead (close, mid-distance, remote fields): no inputs, application of NPK, NP,
NK, or PK fertiliser (urea, triple super phosphate, KCl) to maize. Total soil N decreased at all sites with distance to the
homestead (from 1.30 to 1.06 g kg−1), as did Olsen-P (from 10.5 to 2.3 mg kg−1). Grain yields in the no-input control plots reflected this decrease in soil fertility status with distance to the homestead
(from 2.59 to 1.59 t ha−1). In the NPK treatments, however, this difference between field types disappeared (from 3.43 to 3.98 t ha−1), indicating that N and P are the major limiting nutrients in the target areas. Response to applied N was related to the
soil total N content in Aludeka and Shinyalu, but not in Emuhaia, probably related to the high use of partially decomposed
organic inputs with limited N availability. Consequently, response to applied N decreased with distance to the homestead in
Aludeka (from 0.95 kg kg−1 relative yield to 0.55 kg kg−1) and Shinyalu (from 0.76 kg kg−1 to 0.47 kg kg−1), but not in Emuhaia (from 0.75 kg kg−1 to 0.68 kg kg−1). Response to applied P was related to the soil Olsen-P content at all sites. While for farms with a relatively high Olsen-P
gradient, response to applied P decreased with distance to the homestead (from 0.99 kg kg−1 to 0.68 kg kg−1), large variability in Olsen-P gradients across field types among farms within a specific site often masked clear differences
in response to P between field types for a specific site. Clear scope for field-specific fertiliser recommendations exists,
provided these are based on local soil knowledge and diagnosis. Scenario analysis, using farm-scale modelling tools, could
assist in determining optimum allocation strategies of scarcely available fertiliser for maximum fertiliser use efficiency. 相似文献
13.
S. S. Malhi S. A. Brandt R. Lemke A. P. Moulin R. P. Zentner 《Nutrient Cycling in Agroecosystems》2009,84(1):1-22
A field experiment was conducted from 1995 to 2006 on a Dark Brown Chernozem (Typic Boroll) loam soil at Scott, Saskatchewan,
Canada to determine the influence of input level and crop diversity on accumulation and distribution of nitrate-N and extractable
P in the soil profile, and soil pH, dry aggregation, organic C and N, and nutrient balance sheets in the second 6-year rotation
cycle (2001–2006). Treatments were combinations of three input levels (organic input under conventional tillage—ORG; reduced
input under no-till—RED; and high input under conventional tillage—HIGH), three crop diversities (fallow-based rotations with
low crop diversity—LOW; diversified rotations using annual cereal, oilseed and pulse grain crops—DAG; and diversified rotations
using annual grain and perennial forage crops—DAP), and six crop phases including green manure (GM), chem-fallow or tilled-fallow
(F). Amount of nitrate-N in 0-240 cm soil was usually highest under the HIGH input-LOW crop diversity treatment and lowest
under the ORG input-DAP crop diversity treatment. The distribution of nitrate-N in various soil depths suggested downward
movement of nitrate-N up to 240 cm depth, especially with LOW crop diversity compared to DAP crop diversity, and with HIGH
input. In some years, the ORG input systems had higher nitrate-N than the RED or HIGH input systems, which was attributed
to low extractable P in soil for optimum crop growth and reduced nutrient uptake with ORG input management. Extractable P
in soil was higher by a small margin for HIGH or RED input relative to ORG input in the 0–15 cm layer, suggesting little downward
movement of P. Crop diversity did not affect extractable soil P due to the low baseline levels of P in this soil. The proportion
of fine dry aggregates (<1.3 mm, erodible fraction) in 0–5 cm soil was highest with LOW crop diversity-HIGH input system,
and lowest with DAG diversity-RED input system. The opposite was true for large aggregates (>12.7 mm). Wet aggregate stability
was higher for RED input compared to ORG and HIGH input, which was attributed to the increase in the concentration of organic
C in aggregates in the RED input system. Amount of light fraction organic matter (LFOM), light fraction organic C (LFOC) and
light fraction organic N (LFON) in 0–15 cm soil was higher for RED input compared to ORG and HIGH inputs, and higher for DAG
and DAP crop diversities than for LOW crop diversity. Soil N and P were usually deficient under ORG input management, but
large amounts of N and P were unaccounted for, or in surplus, under RED and HIGH inputs, despite a marked increase in plant
N and P uptake and crop yield compared to ORG input. Overall, our findings suggest that soil quality can be improved and nutrient
accumulation in the soil profile can be minimized by increasing cropping frequency, reducing/eliminating tillage, and using
appropriate combinations of fertilizer input and diversified cropping. 相似文献
14.
Nitrogen,phosphorus, and potassium budgets in Indian agriculture 总被引:1,自引:0,他引:1
Nutrient budgeting is a useful tool in determining present and future productivity of agricultural land as well as undesirable
effects of nutrient mining and environmental pollution. Budgets of N, P, and K were calculated for India for 2000–2001 taking
into consideration the inputs through inorganic fertilizer, animal manure, compost, green manure, leguminous fixation, non-leguminous
fixation, crop residues, rain and irrigation water and outputs through crop uptake and losses through leaching, volatilization
and denitrification. Inorganic fertilizer was the dominant source contributing 64% of N and 78% of P inputs in Indian agriculture,
whereas K input through inorganic fertilizer was 26%. Removals of N, P, and K by major agricultural crops in the country were
7.7, 1.3 and 7.5 Mt, respectively. There were positive balances of N (1.4 Mt) and P (1.0 Mt) and a negative balance of K (3.3 Mt).
It was projected that N, P, and K requirement by Indian agriculture would be 9.78, 1.57 and 9.52 Mt, respectively, to meet
the food demand of 1.3 billion people by 2020. The study identified the ‘hotspots’ of excess nutrient loads as well as of
nutrient mining regions in India to improve our ability to predict environmental degradation due to imbalanced fertilizer
use. However, there are some uncertainties in India’s nutrient budget and more research is required to reduce these uncertainties. 相似文献
15.
More sustainable production of high-quality, nutritious food is of worldwide interest. Increasing nutrient recycling into food systems is a step in this direction. The objective of the present study was to determine nitrogen (N) fertiliser effects of four waste-derived and organic materials in a cropping sequence of broccoli, potato and lettuce grown at two latitudes (58° and 67°N) in Norway during 3 years. Effects of anaerobically digested food waste (AD), shrimp shell (SS), algae meal (AM) and sheep manure (SM) at different N application rates (80 and 170 kg N ha?1 for broccoli, and 80 and 60 kg N ha?1 for potato and lettuce, respectively) and residual effects were tested on crop yield, N uptake, N recovery efficiency (NRE), N balance, N content in produce, mineral N in soil, product quality parameters and content of nitrate in lettuce. Mineral fertiliser (MF) served as control. Effects on yield, N uptake, NRE, N balance and product quality parameters could to a great extent be explained by estimated potentially plant-available N, which ranked in the order of AD > SS > SM > AM. Results for crops fertilised with AD and SS were not significantly different from MF at the same N application rate, while AM, in agreement with its negative effect on N mineralisation, gave negative or near-neutral effects compared to the control. No residual effect was detected after the year of application. The results showed that knowledge about N dynamics of relevant organic waste-derived fertilisers is necessary to decide on the timing and rate of application. 相似文献
16.
K. K. Hazra M. S. Venkatesh P. K. Ghosh A. N. Ganeshamurthy N. Kumar N. Nadarajan A. B. Singh 《Nutrient Cycling in Agroecosystems》2014,100(1):95-110
Given inherent qualities like N-fixation, P-solublization and nutrient recycling pulses remain the most preferred option for diversification of cereal-based rotations. A long-term experiment was used to assess the effect of including pulses in rice–wheat rotation on soil–plant nutrient dynamics under inorganic and organic nutrient management. Results revealed that pulses were equally responsive to organic and inorganic nutrient management while, growth of cereals especially wheat was restricted severely under organic production system due to low nutrient input. The annual input (kg ha?1) of N (103.6–160.8) and P (25.9–34.7) under organic treatment was almost ½ of the recommended inorganic rate, while organics supplied higher K and S. Under organic management, the apparent balance of all the nutrients was negative whereas, inorganic fertilization resulted in positive balance of N, P and Zn. Long-term inclusion of pulses in rice–wheat rotation significantly increased soil organic C and available nutrients thus, increased the nutrient uptake by cereals. Mungbean inclusion in rice–wheat rotation significantly (P ≤ 0.05) increased uptake of N (23.0 %), P (32.9 %) and K (21.1 %) by rice crop. Continuous inorganic fertilization enriched soil available N, P, Zn and B. While organic management maintained higher SOC, available K and S over inorganic treatment. Thus, the study suggested that under organic management N and P nutrition is limiting factor for cereals and needs inorganic supplementation. The study also indicates the need for including pulses in conventional rice–wheat system for optimum nutrient acquisition and long-term soil health management. 相似文献
17.
Identification of nutrients limiting cassava yield maintenance on a sedimentary soil in southern Benin,West Africa 总被引:1,自引:0,他引:1
Market opportunities will drive intensification of cassava production and fertilizer will play a role in this. A trial was initiated on 15 farmers fields (replications) in one village territory in Benin on a relatively fertile sedimentary soil site to identify nutrients limiting cassava yield using nutrient omission plots over three cropping years. There was no response to fertilizer in the first year when fresh root yields in the unamended control averaged 19.1 t ha–1. In the second year, the control yield was 16 t ha–1 and there were significant reductions from withholding P (3.5 t ha–1) and K (2 t ha–1) from a complete fertilizer regime. Nutrient balance after 1 and 2 years (cumulative) showed substantial P and K deficits in unamended plots. In the third year, the control yield was 12.9 t ha–1 and effects of withholding K (5.3 t ha–1), P (5.0 t ha–1) and N (3.0 t ha–1) were statistically significant. Soil K was a significant source of variation in yield in the third year. In the third year of annual nutrient additions soil P and K in the top 0.3 m were increased by 37 and 40%, respectively. Based on the cumulative nutrient balance calculation, the annual application needed to compensate nutrient depletion was 13 kg N, 10 kg P, and 60 kg K ha–1. Partial budget analysis based on these amounts of fertilizer suggested that investment was clearly justified in the third year of continuous cropping at current low cassava prices. 相似文献
18.
Nutrient Uptake and Balance of Cotton + Pigeonpea Strip Intercropping
on Rainfed Vertisols of Central India 总被引:2,自引:0,他引:2
Nutrient uptake and balance of the cotton (Gossypium hirsutum L.) + pigeonpea (Cajanus cajan(L.) Millsp.), a traditional strip intercropping system practiced on the rainfed Vertisols of central India is not known to
us. On-farm participatory trials were conducted on 10 farmer fields, five each on medium deep (MDS) and deep soils (DS) of
Nagpur, central India to determine the effect of technological interventions on N, P and K uptake of cotton and pigeonpea.
The nutrient balance was also quantified as a difference of nutrient inputs and removal. Nutrients accumulated by the crops
(grain, stalk and leaves) and weeds removed off the field by hand weeding were considered as nutrient removal, while fertilizer
was considered as nutrient input. The interventions included application of recommended dose of fertilizer (RDF), RDF + conservation
tillage with in situ green manure (CT1) and CT1 + application of ZnSO4 (CT2) and compared with farmers’ practice (FP). Nutrient uptake, in general, was higher on DS than on MDS. Among the interventions,
N, P and K uptake of cotton and pigeonpea followed the order: CT2 > CT1 > RDF > FP. Mean N and P balance was positive in all the treatments. The balance may become negative if nutrient losses are
accounted. A negative K balance was observed in all the treatments and the magnitude was the greatest for the FP plots (−39.4 kg ha−1 y−1). In spite of fertilizer-K application in the intervention plots, K balance was negative (−14.4 to −19.5 kg ha−1 y−1). By way of leaf and fruit drop, cotton and pigeonpea litter recycled 12.2 kg N, 1.7 kg P and 6.7 kg K ha−1 y−1 相似文献
19.
Crop production in sub-Saharan Africa is constrained by numerous factors including frequent droughts and periods of moisture
stress, low soil fertility, and restricted access to mineral fertilisers. A 2 year (2005/6 and 2006/7) field study was conducted
in Shurugwi district, central Zimbabwe, to determine the effects of different nutrient resources and two tillage practices
on the grain yield of maize (Zea mays L.) and soybean (Glycine max (L.) Merr). Six nutrient resource treatments (control, pit-stored manure, leaf litter, anthill soil, mineral fertiliser,
mineral fertiliser plus pit-stored manure) were combined with two tillage practices (conventional tillage and post-emergence
tied ridging). Basal fertilisation was done with 0 kg ha−1 as control, 240 kg ha−1 PKS fertiliser, 18 t ha−1 manure, 10 t ha−1 manure plus 240 kg ha−1 PKS fertiliser, 35 t ha−1 leaf litter, 52 t ha−1 anthill soil. About 60 kg N/ha was applied to fertiliser only and fertiliser plus manure treatments as top dressing in the
form of ammonium nitrate (34.5%N). A split-plot design was used with nutrient resource as the main plot and tillage practice
as the subplot, and five farmers’ fields were used as replicates. Grain yield was determined at physiological maturity (140
and 126 days after planting for maize and soybean, respectively) and adjusted to 12.5% moisture content for maize and 11%
for soybean. In the first season (2005/06), addition of different nutrient resources under conventional tillage increased
(P < 0.05) maize grain yield by 102–450%, with leaf litter and manure plus fertiliser treatments, giving the lowest (551 kg ha−1) and highest (3,032 kg ha−1) increments, respectively, compared to the control. For each treatment, tied-ridging further increased maize grain yield.
For example, for leaf litter, tied-ridging further increased grain yield by 96% indicating the importance of integrating nutrient
and water management practices in semi-arid areas where moisture stress is frequent. Despite the low rainfall and extended
dry spells in the second season, addition of the different nutrient resources still increased yield which was further increased
by tied-ridging in most treatments. Besides providing grain, soybean had higher residual effects on the following maize crop
compared to Crotalaria gramiana, a green manure. It was concluded that the highest benefits of tied-ridging, in terms of grain yield, were realised when
cattle manure was combined with mineral fertiliser, both of which are available to resource-endowed households. Besides marginally
increasing yield, leaf litter and anthill which represent resources that can be accessed by very poor households, have a positive
effect of the soil chemical environment. 相似文献
20.
The long-term effects of manures and fertilisers on soil productivity and quality: a review 总被引:7,自引:0,他引:7
Douglas C. Edmeades 《Nutrient Cycling in Agroecosystems》2003,66(2):165-180
The results from 14 field trials comparing the long-term (20 to 120 years) effects of fertilisers and manures (farmyard manure, slurry, and green manure) on crop production and soil properties are reviewed. In total there were 24 paired comparisons of the effects of manure and fertiliser. Some of the trials also contained a control (no nutrient inputs) treatment. The input of nutrients as either fertilisers or manures had very large effects (150–1000%) on soil productivity as measured by crop yields. Manured soils had higher contents of organic matter and numbers of microfauna than fertilised soils, and were more enriched in P, K, Ca and Mg in topsoils and nitrate N, Ca and Mg in subsoils. Manured soils also had lower bulk density and higher porosity, hydraulic conductivity and aggregate stability, relative to fertilised soils. However, there was no significant difference (P < 0.05) between fertilisers and manures in their long-term effects on crop production. In the context of this set of international trials, the recent evidence from the Rothamsted classical long-term trials appears to be exceptional, due to the larger inputs of manures and larger accumulation of soil OM in these trials. It is suggested therefore that manures may only have a benefit on soil productivity, over and above their nutrient content, when large inputs are applied over many years. The evidence from these trials also shows that, because the ratio of nutrients in manures is different from the ratio of nutrients removed by common crops, excessive accumulation of some nutrients, and particularly P and N, can arise from the long-term use of manures, relative to the use of fertilisers. Under these conditions greater runoff of P, and leaching of N may result, and for soils with low P retention and/or in situations where organic P is leached, greater P leaching losses may occur. The use of manures, relative to fertilisers, may also contribute to poor water quality by increasing its chemical oxygen demand. It is concluded therefore that it cannot generally be assumed that the long-term use of manures will enhance soil quality – defined in terms of productivity and potential to adversely affect water quality – in the long term, relative to applying the same amounts of nutrients as fertiliser. 相似文献