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1.
Double-cropping annual ryegrass and bermudagrass to reduce phosphorus levels in soil with history of poultry litter application 总被引:1,自引:0,他引:1
J. J. Read K. R. Sistani J. L. Oldham G. E. Brink 《Nutrient Cycling in Agroecosystems》2009,84(1):93-104
Long-term application of poultry litter may result in excessively high soil phosphorus (P). This field study determined the
potential of ‘Coastal’ bermudagrass overseeded with ‘Marshall’ annual ryegrass and harvested for hay to reduce the level of
Mehlich-3 extractable P (M3-P) that had accumulated in a Savannah soil due to a 30-year history of broiler litter application
to bermudagrass, as well as antecedent litter rates of 0, 4.48, 8.96, 17.9, and 35.8 Mg ha−1 in 1999–2001. Following the cessation of litter, the plots were overseeded in fall 2001–2003 and fertilized in summer with
268 kg N ha−1 as NH4NO3. Applying 8.96 Mg ha−1 litter significantly elevated M3-P in surface soil (0–15 cm depth) from about 183 to 263 mg kg−1. Annual dry matter (DM) yield and P uptake generally increased as litter rate increased up to 17.9 Mg ha−1. Analysis of M3-P at four sampling dates from October 2002 to April 2004 found no significant effect of forage system or
its interaction with litter rate, and levels in both systems decreased by about 25, 27, 22, 26, and 29% at the five litter
rates, respectively. Ryegrass–bermudagrass significantly increased DM yield and P uptake, but did not translate to reductions
in M3-P, as compared to bermudagrass winter fallow. With no further litter additions and five harvests per year, both forage
systems removed about 49 kg ha−1 P with a DM yield of 15 Mg ha−1 and reduced M3-P by about 26 mg kg−1 annually. Bermudagrass performance is important in the remediation of high soil P.
相似文献
J. J. ReadEmail: |
2.
Frank Eulenstein Armin Werner Matthias Willms Radosław Juszczak Sandro Luis Schlindwein Bogdan H. Chojnicki Janusz Olejnik 《Nutrient Cycling in Agroecosystems》2008,82(1):33-49
Oxidation of pyrite by nitrate (autotrophic denitrification) was identified as the main cause for sulfate increase in drinking
water wells in an agriculturally used watershed, located in the north of Lower Saxony (Germany). Nitrate, which inducts this
microbial catalyzed process, is drained into ground water predominantly from agricultural fertilization. The increase of sulfate
in the ground water can only be stopped by reducing nitrate leaching into the ground water. To analyze the negative influence
of agricultural fertilization on the quality of ground water different fertilization strategies were deducted for an investigated
area of 890 ha. Calculated on the basis of nutrient balance of soil surface, the current average nitrogen balance in the investigated
area amounts to 91 kg N ha-1 a−1. Farm-gate balance of nutrients is a strong indicator for assessing potential nutrient losses caused by leaching. This indicator
shows comparable accuracy to the calculated nutrient balance of soil surface which demands, however, much more data input
for calculations. Nitrate concentrations in seepage water in 2 m depth layer of the soil from agricultural fields were simulated
with the model HERMES for the whole investigated area (agricultural land + forest). The nitrate concentration in seepage water
was calculated for the whole area on the basis of farm-gate nutrient balance as an annual average, which amounts to 14.0 mg NO3–N l−1 (62 mg NO3 l−1). In order to keep the nitrate concentration of the ground water below the threshold value for drinking water (EU-water directive:
11.3 mg NO3–N l−1 (50 mg NO3 l−1) and to limit pyrite oxidation, different scenarios with simulation studies to optimize fertilization measures were developed.
Only those scenarios which assured reduction of an average nitrate concentration in the drainage water below 11.3 mg NO3–N l−1 (50 mg NO3 l−1) without profit cuts for the farms were analyzed.
相似文献
Janusz OlejnikEmail: |
3.
Under semiarid conditions the response of crops to synthetic fertilizers is often reduced. Organic fertilizers can be used
to provide a continuous source of nutrients for the crops. The soil nitrogen and crop yield in a rotation of durum wheat (Triticum durum)–fallow-barley (Hordeum vulgare)–vetch (Vicia sativa) were studied during 4 years when synthetic fertilizer (chemical), compost (organic) or no fertilizer (control) were applied
in a field with high initial contents of soil NO3–N (> 400 kg N ha−1), phosphorus (22 mg kg−1) and potassium (> 300 mg kg−1). Changes in soil organic matter, phosphorus and potassium were also measured. During the crop period, chemical fertilization
significantly increased the content of soil NO3–N in the first 0.30 m of soil with respect to organic fertilization and the control. The yield of wheat and barley was not
increased after applying chemical or organic fertilizer with respect to the unfertilized plots. The estimated losses of nitrogen
were similar for the three types of fertilization, as well as the uptake of nitrogen for the total biomass produced. The initial
levels of organic matter and phosphorus were maintained, even in the plots that were not fertilized, while the potassium decreased
slightly. Thus, the rotation and burying of crop residues were enough to maintain the crop yield and the initial content of
nutrients. 相似文献
4.
Gueorgui Anguelov Ivanka Anguelova Nathaniel O. Bailey 《Nutrient Cycling in Agroecosystems》2011,90(2):171-187
Land use management is important to maximize nutrients use efficiency and reduce losses, especially on sandy soils. Nutrient
cycling in pastoral systems is different as the grazing animals are excreting back to the pasture most of the ingested nutrients.
The objective of this study was to evaluate N, P, K, Ca, Mg, and Na by monitoring elements’ concentrations in soil solution
from bahiagrass (Paspalum notatum Flugge) pastures continually-stocked with cattle (CP) and rotationally-grazed by goats (GP) in comparison with arable land
(AL). Samples were obtained by suction cup lysimeters randomly installed at three depths in an Ultisol of North Florida, USA.
To evaluate nutrients in atmospheric deposition, surface and ground waters, samples from rain, nearby spring, lake and three
wells on the farm were also analyzed. The results confirmed that land-use management had an effect on soil-solution N, P,
K, Ca, Mg, and Na concentrations reflecting managerial and climatic conditions. The means of these nutrients ranged widely
from 0.64 to 11.14 mg L−1 for N, 0.03–0.45 mg L−1 for P, 0.12–6.97 mg L−1 for K, 0.37–33.91 mg L−1 for Ca, 0.47–7.39 mg L−1 for Mg, and 1.28–4.37 mg L−1 for Na. The soil-solution N was higher from March through August (wet seasons) and lower and relatively constant between
September and February (dry seasons). The N from shallow depth (0.6 m) of CP was fourfold higher than the deep (1.8 m) one
and exceeded the maximum permissible level (MPL) of 10 mg L−1. A 1.5-fold increase by depth of AL was detected, and a leaching of 53–98 kg N ha−1 was identified for both AL and CP during the wet season vs. 4–5 kg ha−1 leachable N from GP. Also, a 1–3 kg P ha−1 may be leached from CP during the wet season. The nutrients in the soil solutions tended to be higher than those in rain,
lake, sprint, well, and tap waters. In groundwater however, there were episodically N concentrations as high as those in the
soil solution. 相似文献
5.
E. N. Masvaya J. Nyamangara R. W. Nyawasha S. Zingore R. J. Delve K. E. Giller 《Nutrient Cycling in Agroecosystems》2010,88(1):111-120
Variability of soil fertility within, and across farms, poses a major challenge for increasing crop productivity in smallholder
systems of sub-Saharan Africa. This study assessed the effect of farmers’ resource endowment and nutrient management strategies
on variability in soil fertility and plant nutrient uptake between different fields in Gokwe South (ave. rainfall ~650 mm year−1; 16.3 persons km−2) and Murewa (ave. rainfall ~850 mm year−1; 44.1 persons km−2) districts, Zimbabwe. In Murewa, resource-endowed farmers applied manure (>3.5 t ha−1 year−1) on fields closest to their homesteads (homefields) and none to fields further away (outfields). In Gokwe the manure was
not targeted to any particular field, and farmers quickly abandoned outfields and opened up new fields further way from the
homestead once fertility had declined, but homefields were continually cultivated. Soil available P was higher in homefields
(8–13 mg kg−1) of resource-endowed farmers than on outfields and all fields on resource constrained farms (2–6 mg kg−1) in Murewa. Soil fertility decreased with increasing distance from the homestead in Murewa while the reverse trend occurred
in Gokwe South, indicating the impact of different soil fertility management strategies on spatial soil fertility gradients.
In both districts, maize showed deficiency of N and P, implying that these were the most limiting nutrients. It was concluded
that besides farmers’ access to resources, the direction of soil fertility gradients also depends on agro-ecological conditions
which influence resource management strategies. 相似文献
6.
Mineralizable soil nitrogen and labile soil organic matter in diverse long-term cropping systems 总被引:3,自引:0,他引:3
John T. Spargo Michel A. Cavigelli Steven B. Mirsky Jude E. Maul John J. Meisinger 《Nutrient Cycling in Agroecosystems》2011,90(2):253-266
Sustainable soil fertility management depends on long-term integrated strategies that build and maintain soil organic matter
and mineralizable soil N levels. These strategies increase the portion of crop N needs met by soil N and reduce dependence
on external N inputs required for crop production. To better understand the impact of management on soil N dynamics, we conducted
field and laboratory research on five diverse management systems at a long-term study in Maryland, the USDA- Agricultural
Research Service Beltsville Farming Systems Project (FSP). The FSP is comprised of a conventional no-till corn (Zea mays L.)–soybean (Glycine max L.)–wheat (Triticum aestivum L.)/double-crop soybean rotation (NT), a conventional chisel-till corn–soybean–wheat/soybean rotation (CT), a 2 year organic
corn–soybean rotation (Org2), a 3 year organic corn–soybean–wheat rotation (Org3), and a 6 year organic corn–soybean–wheat–alfalfa
(Medicago sativa L.) (3 years) rotation (Org6). We found that total potentially mineralizable N in organic systems (average 315 kg N ha−1) was significantly greater than the conventional systems (average 235 kg N ha−1). Particulate organic matter (POM)–C and –N also tended to be greater in organic than conventional cropping systems. Average
corn yield and N uptake from unamended (minus N) field microplots were 40 and 48%, respectively, greater in organic than conventional
grain cropping systems. Among the three organic systems, all measures of N availability tended to increase with increasing
frequency of manure application and crop rotation length (Org2 < Org3 ≤ Org6) while most measures were similar between NT
and CT. Our results demonstrate that organic soil fertility management increases soil N availability by increasing labile
soil organic matter. Relatively high levels of mineralizable soil N must be considered when developing soil fertility management
plans for organic systems. 相似文献
7.
Application of manure to no-till soils: phosphorus losses by sub-surface and surface pathways 总被引:2,自引:0,他引:2
Peter J. A. Kleinman Andrew N. Sharpley Lou S. Saporito Anthony R. Buda Ray B. Bryant 《Nutrient Cycling in Agroecosystems》2009,84(3):215-227
The acceleration of surface water eutrophication attributed to agricultural runoff has focused attention on manure management
in no-till. We evaluated losses of phosphorus (P) in sub-surface and surface flow as a function of dairy manure application
to no-till soils in north-central Pennsylvania. Monitoring of a perennial spring over 36 months revealed that dissolved reactive
P (DRP) concentrations increased 3- to 28-fold above background levels whenever manure was broadcast to nearby field soils.
A study conducted with 30-cm deep intact soil cores indicated that incorporation of manure by tillage lowered P loss in leachate
relative to broadcast application, presumably due to the destruction of preferential flow pathways. More P was leached from
a sandy loam than a clay loam soil, although differences between soils were not as great as differences between application
methods. In contrast, rainfall simulations on 2-m2 field runoff plots showed that total P (TP) losses in surface runoff differed significantly by soil but not by application
method. Forms of P in surface runoff did change with application method, with DRP accounting for 87 and 24% of TP from broadcast
and tilled treatments, respectively. Losses of TP in leachate from manured columns over 7 weeks (0.22–0.38 kg P ha−1) were considerably lower than losses in surface runoff from manured plots subjected to a single simulated rainfall event
(0.31–2.07 kg TP ha−1). Results confirm the near-term benefits of incorporating manure by tillage to protect groundwater quality, but suggest that
for surface water quality, avoiding soils prone to runoff is more important.
相似文献
Peter J. A. KleinmanEmail: |
8.
In southern Africa, tillage research has focused on rainfed smallholder cropping systems, while literature on high-input irrigated
cropping systems is limited. We evaluated the effects of conventional (CT), minimum (MT) and no-till (NT) tillage systems
on soil organic carbon (SOC), bulk density, water-stable aggregates (WSA), mean weighted diameter (MWD) and crop yields in
an irrigated wheat–cotton rotation. Soil data were monitored in the first and final year, while yields were monitored seasonally.
Average bulk densities (1.5–1.7 Mg m−3) were similar among tillage systems, but often exceeded the critical limit (1.60 Mg m−3) for optimum root growth. Conversion from CT to MT and NT failed to ameliorate the high bulk densities associated with the
alluvial soil. SOC (g kg−1) at 0–15 cm was higher (P < 0.05) under MT (3.9–5.8) and NT (4.2–5.6) than CT (2.9–3.3). Corresponding horizon SOC stocks (Mg C ha−1) for the tillage treatments were; 9.3–13.9 (MT), 9.3–13.5 (NT) and 7.3–7.7 (CT). In the final year, significant (P < 0.05) tillage effects on SOC stocks were also observed at 15–30 cm. Cumulative SOC stocks (Mg C ha−1) in the 0–60 cm profile were higher (P < 0.05) under MT (32.8–39.9) and NT (32.9–41.6) than CT (27.8–30.9). On average, MT and NT sequestered between 0.55 and 0.78 Mg C ha−1 year−1 at 0–30 cm depth, but a net decline (0.13 Mg C ha−1 year−1) was observed under CT. At 0–30 cm, MT and NT had higher (P < 0.05) MWD (0.19–0.23 mm) and WSA (2.3–3.5%) than CT (MWD: 0.1–0.12 mm, WSA: ≈1.0%). Both MWD and WSA were significantly
(P < 0.05) correlated to SOC. Seasonal yields showed significant (P < 0.05) tillage effects, but 6-year mean yields (t ha−1) were similar (CT: 4.49, MT: 4.33, NT: 4.32 for wheat; CT: 3.30, MT: 2.82, NT: 2.83 for cotton). Overall, MT and NT improved
soil structural stability and carbon sequestration, while impacts on crop productivity were limited. Therefore, MT and NT
are more sustainable tillage systems for the semi-arid regions than conventional tillage.
S. Chakanetsa—Deceased. 相似文献
9.
Cynthia A. Cambardella Thomas B. Moorman Jeremy W. Singer 《Nutrient Cycling in Agroecosystems》2010,87(3):383-393
Coupling winter small grain cover crops (CC) with manure (M) application may increase retention of manure nitrogen (N) in
corn (Zea mays L.), -soybean [Glycine max (L.) Merr], cropping systems. The objective of this research was to quantify soil N changes after application of liquid swine
M (Sus scrofa L.) at target N rates of 112, 224, and 336 kg N ha−1 with and without a CC. A winter rye (Secale cereale L.)-oat (Avena sativa L.) CC was established prior to fall M injection. Surface soil (0–20 cm) inorganic N concentrations were quantified every
week for up to 6 weeks after M application in 2005 and 2006. Soil profile (0–120 cm in 5, 20-cm depth increments) inorganic
N, total N, total organic carbon and bulk density were quantified for each depth increment in the fall before M application
and before the CC was killed the following spring. Surface soil inorganic N on the day of application averaged
318 \textmg \textN \textkg - 1\textsoil 318\,{\text{mg}}\;{\text{N}}\;{\text{kg}}^{ - 1}{_{\text{soil}}} in 2005 and
186 \textmg \textN \textkg - 1\textsoil 186\,{\text{mg}}\;{\text{N}}\;{\text{kg}}^{ - 1}{_{\text{soil}} } in 2006 and stabilized at
150 \textmg \textN \textkg - 1\textsoil 150\,{\text{mg}}\;{\text{N}}\;{\text{kg}}^{ - 1}{_{\text{soil}}} in both years by mid-November. Surface soil NO3-N concentrations in the M band were more than 30 times higher in the fall of 2005 than in 2006. The CC reduced surface soil
NO3-N concentrations after manure application by 32% and 67% in mid- November 2005 and 2006, respectively. Manure applied at
224 kg N ha−1 without a CC had significantly more soil profile inorganic-N (480 kg N ha−1) in the spring after M application than manured soils with a CC for the 112 (298 kg N ha−1) and 224 (281 kg N ha−1) N rates, and equivalent inorganic N to the 336 (433 kg N ha−1) N rate. These results quantify the potential for cover crops to enhance manure N retention and reduce N leaching potential
in farming systems utilizing manure. 相似文献
10.
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
11.
C. L. van Beek M. Pleijter C. M. J. Jacobs G. L. Velthof J. W. van Groenigen P. J. Kuikman 《Nutrient Cycling in Agroecosystems》2010,86(3):331-340
Intensively managed grasslands on organic soils are a major source of nitrous oxide (N2O) emissions. The Intergovernmental Panel on Climate Change (IPCC) therefore has set the default emission factor at 8 kg N–N2O ha−1 year−1 for cultivation and management of organic soils. Also, the Dutch national reporting methodology for greenhouse gases uses
a relatively high calculated emission factor of 4.7 kg N–N2O ha−1 year−1. In addition to cultivation, the IPCC methodology and the Dutch national methodology account for N2O emissions from N inputs through fertilizer applications and animal urine and faeces deposition to estimate annual N2O emissions from cultivated and managed organic soils. However, neither approach accounts for other soil parameters that might
control N2O emissions such as groundwater level. In this paper we report on the relations between N2O emissions, N inputs and groundwater level dynamics for a fertilized and grazed grassland on drained peat soil. We measured
N2O emissions from fields with different target groundwater levels of 40 cm (‘wet’) and 55 cm (‘dry’) below soil surface in
the years 1992, 1993, 2002, 2006 and 2007. Average emissions equalled 29.5 kg N2O–N ha−1 year−1 and 11.6 kg N–N2O ha−1 year−1 for the dry and wet conditions, respectively. Especially under dry conditions, measured N2O emissions exceeded current official estimates using the IPCC methodology and the Dutch national reporting methodology. The
N2O–N emissions equalled 8.2 and 3.2% of the total N inputs through fertilizers, manure and cattle droppings for the dry and
wet field, respectively and were strongly related to average groundwater level (R
2 = 0.74). We argue that this relation should be explored for other sites and could be used to derive accurate emission data
for fertilized and grazed grasslands on organic soils. 相似文献
12.
Influence of organic amendments on growth, yield and quality of wheat and on soil properties during transition to organic production 总被引:3,自引:0,他引:3
K. A. Gopinath Supradip Saha B. L. Mina Harit Pande S. Kundu H. S. Gupta 《Nutrient Cycling in Agroecosystems》2008,82(1):51-60
A transition period of at least 2 years is required for annual crops before the produce may be certified as organically grown.
The purpose of this study was to evaluate the effects of three organic amendments on the yield and quality of wheat (Triticum aestivum L.) and on soil properties during transition to organic production. The organic amendments were composted farmyard manure
(FYMC), vermicompost and lantana (Lantana spp. L.) compost applied to soil at four application rates (60 kg N ha−1, 90 kg N ha−1, 120 kg N ha−1 and 150 kg N ha−1). The grain yield of wheat in all the treatments involving organic amendments was markedly lower (36–65% and 23–54% less
in the first and second year of transition, respectively) than with the mineral fertilizer treatment. For the organic treatments
applied at equivalent N rates, grain yield was higher for FYMC treatment, closely followed by vermicompost. In the first year
of transition, protein content of wheat grain was higher (85.9 g kg−1) for mineral fertilizer treatment, whereas, in the second year, there were no significant differences among the mineral fertilizer
treatment and the highest application rate (150 kg N ha−1) of three organic amendments. The grain P and K contents were, however, significantly higher for the treatments involving
organic amendments than their mineral fertilizer counterpart in both years. Application of organic amendments, irrespective
of source and rate, greatly lowered bulk density (1.14–1.25 Mg m−3) and enhanced pH (6.0–6.5) and oxidizable organic carbon (13–18.8 g kg−1) of soil compared with mineral fertilizer treatment after a 2-year transition period. Mineral fertilized plots, however,
had higher levels of available N and P than plots with organic amendments. All the treatments involving organic amendments,
particularly at higher application rates, enhanced soil microbial activities of dehydrogenase, β-glucosidase, urease and phosphatase
compared with the mineral fertilizer and unamended check treatments. We conclude that the application rate of 120 kg N ha−1 and 150 kg N ha−1 of all the three sources of organic amendments improved soil properties. There was, however, a 23–65% reduction in wheat
yield during the 2 years of transition to organic production. 相似文献
13.
J. Kihara A. Bationo D. N. Mugendi C. Martius P. L. G. Vlek 《Nutrient Cycling in Agroecosystems》2011,90(2):213-225
Smallholder land productivity in drylands can be increased by optimizing locally available resources, through nutrient enhancement
and water conservation. In this study, we investigated the effect of tillage system, organic resource and chemical nitrogen
fertilizer application on maize productivity in a sandy soil in eastern Kenya over four seasons. The objectives were to (1)
determine effects of different tillage-organic resource combinations on soil structure and crop yield, (2) determine optimum
organic–inorganic nutrient combinations for arid and semi-arid environments in Kenya and, (3) assess partial nutrient budgets
of different soil, water and nutrient management practices using nutrient inflows and outflows. This experiment, initiated
in the short rainy season of 2005, was a split plot design with 7 treatments involving combinations of tillage (tied-ridges,
conventional tillage and no-till) and organic resource (1 t ha−1 manure + 1 t ha−1 crop residue and; 2 t ha−1 of manure (no crop residue) in the main plots. Chemical nitrogen fertilizer at 0 and 60 kg N ha−1 was used in sub-plots. Although average yield in no-till was by 30–65% lower than in conventional and tied-ridges during
the initial two seasons, it achieved 7–40% higher yields than these tillage systems by season four. Combined application of
1 t ha−1 of crop residue and 1 t ha−1 of manure increased maize yield over sole application of manure at 2 t ha−1 by between 17 and 51% depending on the tillage system, for treatments without inorganic N fertilizer. Cumulative nutrients
in harvested maize in the four seasons ranged from 77 to 196 kg N ha−1, 12 to 27 kg P ha−1 and 102 to 191 kg K ha−1, representing 23 and 62% of applied N in treatments with and without mineral fertilizer N respectively, 10% of applied P
and 35% of applied K. Chemical nitrogen fertilizer application increased maize yields by 17–94%; the increases were significant
in the first 3 seasons (P < 0.05). Tillage had significant effect on soil macro- (>2 mm) and micro-aggregates fractions (<250 μm >53 μm: P < 0.05), with aggregation indices following the order no-till > tied-ridges > conventional tillage. Also, combining crop
residue and manure increased large macro-aggregates by 1.4–4.0 g 100 g−1 soil above manure only treatments. We conclude that even with modest organic resource application, and depending on the number
of seasons of use, conservation tillage systems such as tied-ridges and no-till can be effective in improving crop yield,
nutrient uptake and soil structure and that farmers are better off applying 1 t ha−1 each of crop residue and manure rather than sole manure. 相似文献
14.
C. L. van Beek C. van der Salm A. C. C. Plette H. van de Weerd 《Nutrient Cycling in Agroecosystems》2009,83(2):99-110
Agriculture is a main contributor of diffuse emissions of N and P to the environment. For N the main loss pathways are NH3-volatilization, leaching to ground and surface water and N2(O) emissions. Currently, imposing restraints on farm inputs are used as policy tool to decrease N and P leaching to ground
water and to surface water, and the same measure is suggested to combat emissions of N2O. The response, however, to these measures largely depends on the soil type. In this study nutrient flows of three dairy
farms in The Netherlands with comparable intensity on sand, peat and clay soils were monitored for at least 2 years. The first
aim was to provide quantitative data on current nutrient loss pathways. The second aim was to explore the responses in partitioning
of the nutrient loss pathways when farm inputs were altered. Mean denitrification rates ranged from 103 kg N ha−1 year−1 for the sandy soil to 170 kg N ha−1 year−1 for the peat soil and leaching to surface water was about 73 kg N ha−1 year−1 for the sandy soil, 15 kg N ha−1 year−1 for the clay soil and 38 kg N ha−1 year−1 for the peat soil. For P, leaching to surface water ranged from 2 kg P ha−1 year−1 for the sandy site to 5 kg P ha−1 year−1 for the peat site. The sandy soil was most responsive to changes in N surpluses on leaching to surface water, followed by
the peat soil and least responsive was the clay soil. For P, a similar sequence was found. This article demonstrates that
similar reductions of N and P inputs result in different responses in N and P loss pathways for different soil types. These
differences should be taken into account when evaluating measures to improve environmental performance of (dairy) farms. 相似文献
15.
Sarah M. Stackpoole Kevin R. Kosola Beth Ann A. Workmaster Nathan M. Guldan Bryant A. Browne Randall D. Jackson 《Nutrient Cycling in Agroecosystems》2011,91(1):41-54
Even though nitrogen (N) is a key nutrient for successful cranberry production, N cycling in cranberry agroecosystems is not
completely understood. Prior research has focused mainly on timing and uptake of ammonium fertilizer, but the objective of
our study was to evaluate the potential for additional N contributions from hydrologic inputs (flooding, irrigation, groundwater,
and precipitation) and organic matter (OM). Plant biomass, soil, surface and groundwater samples were collected from five
cranberry beds (cranberry production fields) on four different farms, representing both upland and lowland systems. Estimated
average annual plant uptake (63.3 ± 22.5 kg N ha−1 year−1) exceeded total average annual fertilizer inputs (39.5 ± 11.6 kg N ha−1 year−1). Irrigation, precipitation, and floodwater N summed to an average 23 ± 0.7 kg N ha−1 year−1, which was about 60% of fertilizer N. Leaf and stem litterfall added 5.2 ± 1.2 and 24.1 ± 3.0 kg N ha−1 year−1 respectively. The estimated net N mineralization rate from the buried bag technique was 5 ± 0.2 kg N ha−1 year−1, which was nearly 15% of fertilizer N. Dissolved organic nitrogen represented a significant portion of the total N pool in
both surface water and soil samples. Mixed-ion exchange resin core incubations indicated that 80% of total inorganic N from
fertilizer, irrigation, precipitation, and mineralization was nitrate, and approximately 70% of recovered inorganic N from
groundwater was nitrate. There was a weak but significant negative relationship between extractable soil ammonium concentrations
and ericoid mycorrhizal colonization (ERM) rates (r = −0.22, P < 0.045). Growers may benefit from balancing the N inputs from hydrologic sources and OM relative to fertilizer N in order
to maximize the benefits of ERM fungi in actively mediating N cycling in cranberry agroecosystems. 相似文献
16.
Horizontal nutrient flows and balances in irrigated urban gardens of Khartoum, Sudan 总被引:1,自引:1,他引:0
Sahar Babiker Abdalla Martina Predotova Jens Gebauer Andreas Buerkert 《Nutrient Cycling in Agroecosystems》2012,92(2):119-132
The role of urban agriculture (UA) for the supply of fresh vegetables, fruits and meat for local markets is well known. The
periodically flooded Gerif soils on the River Nile banks in the core of Khartoum city harbour vegetable gardens that supply perishable leafy vegetables
with a short life cycle. In an effort to assess their sustainability and possible negative environmental impact we used a
horizontal balance approach to determine the nutrient use efficiency of four intensively cropped UA gardens. Two of the gardens
were located in downstream lowlands (L1 and L2) and the other two belonged to the upstream highlands (H1 and H2). The river
sediments contributed on average 873 kg nitrogen (N), 6.5 kg phosphorus (P), 6.8 kg potassium (K) and 8,317 kg carbon (C)
per hectare in lowland gardens, while only 289, 1.6, 2.5 and 1,938 kg N, P, K and C ha−1 reached the highlands. The farmers’ management in all four gardens resulted in horizontal N and C surpluses of 75–342 kg N ha−1 year−1 and 798–6,412 kg C ha−1 year−1, in contrast to P and K for which negative balances up to −45 kg P ha−1 year−1 and −583 kg K ha−1 year−1 were recorded. While the River Nile floods as important N and C source contribute significantly to soil fertility maintenance,
the negative P and K balances call for a better integration of UA gardening with livestock husbandry and the regular addition
of animal manure in these cropping systems. 相似文献
17.
Gilbert C. Sigua Robert K. Hubbard Samuel W. Coleman Mimi Williams 《Nutrient Cycling in Agroecosystems》2010,86(2):175-187
Despite substantial measurements using both laboratory and field techniques, little is known about the spatial and temporal
variability of nitrogen (N) dynamics across the landscapes, especially in agricultural landscapes with cow–calf operations.
This study was conducted to assess the comparative levels of total inorganic nitrogen, TIN (NO3–N + NH4–N) among soils, forage, surface water and shallow groundwater (SGW) in bahiagrass (Paspalum notatum, Flueggé) pastures. Soil samples were collected at 0–20, 20–40, 40–60, and 60–100 cm across the pasture’s landscape (top
slope, TS; middle slope, MS; and bottom slope, BS) in the spring and fall of 2004, 2005 and 2006, respectively. Bi-weekly
(2004–2006) groundwater and surface water samples were taken from wells located at TS, MS, and BS and from the run-off/seepage
area (SA). Concentrations of NH4–N, NO3–N, and TIN in SGW did not vary with landscape position (LP). However, concentrations of NH4–N, NO3–N, and TIN in water samples collected from the seep area were significantly (P ≤ 0.05) higher when compared to their average concentrations in water samples collected from the different LP. Average concentrations
of NO3–N (0.4–0.9 mg l−1) among the different LP were well below the maximum, of 10 mg l−1, set for drinking water. The maximum NO3–N concentrations (averaged across LP) in SGW for 2004, 2005 and 2006 were also below the drinking water standards for NO3–N. Concentration of TIN in soils varied significantly (P ≤ 0.05) with LP and soil depth. Top slope and surface soil (0–20 cm) had the greatest concentrations of TIN. The greatest
forage availability of 2,963 ± 798 kg ha−1 and the highest N uptake of 56 ± 12 kg N ha−1 were observed from the TS in 2005. Both forage availability and N uptake of bahiagrass at the BS were consistently the lowest
when averaged across LP and years. These results can be attributed to the grazing activities as animals tend to graze more
at the BS. The average low soil test value of TN (across LP and soil depth) in our soils of 10.9 mg kg−1 (5.5 kg N ha−1) would indicate that current pasture management including cattle rotation in terms of grazing days and current fertilizer
application (inorganic + feces + urine) for bahiagrass pastures may not have negative impact on the environment. 相似文献
18.
Soil nitrate-N levels required for high yield maize production in the North China Plain 总被引:4,自引:0,他引:4
Zhenling Cui Fusuo Zhang Yuxin Miao Qinping Sun Fei Li Xinping Chen Junliang Li Youliang Ye Zhiping Yang Qiang Zhang Chunsheng Liu 《Nutrient Cycling in Agroecosystems》2008,82(2):187-196
High profile nitrate-nitrogen (N) accumulation has caused a series of problems, including low N use efficiency and environmental
contamination in intensive agricultural systems. The key objective of this study was to evaluate summer maize (Zea mays L.) yield and N uptake response to soil nitrate-N accumulation, and determine soil nitrate-N levels to meet N demand of high
yield maize production in the North China Plain (NCP). A total of 1,883 farmers’ fields were investigated and data from 458
no-N plots were analyzed in eight key maize production regions of the NCP from 2000 to 2005. High nitrate-N accumulation (≥172 kg N ha−1) was observed in the top (0–90 cm) and deep (90–180 cm) soil layer with farmers’ N practice during maize growing season.
Across all 458 no-N plots, maize grain yield and N uptake response to initial soil nitrate-N content could be simulated by
a linear plus plateau model, and calculated minimal pre-planting soil nitrate-N content for maximum grain yield and N uptake
was 180 and 186 kg N ha−1, respectively, under no-N application conditions. Economically optimum N rate (EONR) decreased linearly with increasing pre-planting
soil nitrate-N content (r
2 = 0.894), and 1 kg soil nitrate-N ha−1 was equivalent to 1.23 kg fertilizer-N ha−1 for maize production. Residual soil nitrate-N content after maize harvest increased exponentially with increasing N fertilizer
rate (P < 0.001), and average residual soil nitrate-N content at the EONR was 87 kg N ha−1 with a range from 66 to 118 kg N ha−1. We conclude that soil nitrate-N content in the top 90 cm of the soil profile should be maintained within the range of 87–180 kg N ha−1 for high yield maize production. The upper limit of these levels would be reduce if N fertilizer was applied during maize
growing season. 相似文献
19.
Nizar Tlili Taissir El Guizani Nizar Nasri Abdelhamid Khaldi Saida Triki 《Journal of the American Oil Chemists' Society》2011,88(2):265-270
Capparis spinosa has a large natural distribution over the Mediterranean basin. It is used in traditional medicines, and it is one of the
most commonly found aromatics in the Mediterranean kitchen. In this paper, the total storage protein and lipids of Tunisian
Capparis spinosa seeds were investigated, and the quantities were ca. 27% and ca. 33%, respectively. In this study also the composition of
the aliphatic and triterpenic alcohols of C. spinosa was characterized for the first time. Aliphatic alcohol contents were ca. 45 mg kg−1 of total extracted lipids. Three compounds were identified, hexadecanol, octadecanol and tetracosanol, of which octadecanol
was the major compound (ca. 28 mg kg−1). Triterpenic alcohol content was 396.82 mg kg−1. Citrostadienol was the major compound (ca. 170 mg kg−1). β-Amyrin, gramisterol, cycloartanol and 2,4 methylcycloartenol were also detected and identified. 相似文献
20.
Effects of fertilization on nutrient budget and nitrogen use efficiency of farmland soil under different precipitations in Northeastern China 总被引:3,自引:0,他引:3
Qiang Ma Wan-Tai Yu Shan-Min Shen Hua Zhou Zi-Shao Jiang Yong-Gang Xu 《Nutrient Cycling in Agroecosystems》2010,88(3):315-327
Based on a consecutive 16-year field trial and meteorological data, the effects of fertilization on the nutrient budget and
nitrogen use efficiency in farmland soil under different precipitation years were studied. With no fertilization treatment,
the grain yield of maize was 3,520 kg ha−1 (mean yield over 13 years). But the maximum yield increased to 7,470 kg ha−1 when treated with mineral N, P and K fertilizers and recycled manure. The nutrient uptake also increased by twofold to threefold
in NPKM treated field compared with that in the control treatment. The highest yields were obtained in years with normal precipitation,
despite the different fertilization schemes. The lowest yields were obtained in drought or waterlogging years, which were
44.7–58.5% of the yields in years with normal precipitation. It also appeared that the deficits of N, P and K were greater
in the years with proper precipitation than those in arid or flood years, because more production was removed from the field.
Soil total N decreased significantly when treated with mineral fertilizer or recycled manure alone. The maximum deficit of
soil total N was observed in control treatment (557 kg ha−1) from 1990 to 2005. The N treatment resulted in a significant negative balance of P, due to the high yield of the crop in
response to applied N. The application of NP or N to soils resulted in a greater negative K balance than that of the control.
The greatest negative balance of total P and available P were obtained under the control and N treatment, and the highest
deficit of soil total K and exchangeable K were obtained under NP treatment. We found that the rate of 150 kg N ha−1 year−1 was inadequate for maintaining soil N balance, and amendment of soil with organic source could not stop the loss of soil
P and K. The applying rates of 150 kg N ha−1 year−1, 25 kg P ha−1 year−1, and 60 kg K ha−1 year−1 combined with 2–3 t ha−1 organic manure were recommended to maintain soil fertility level. The nitrogen use efficiency (NUE) was greatly improved
in the years with proper precipitation and balanced fertilization. Higher NUE and grain yields were achieved under NPK and
NPKM treatments in years with normal precipitation. The results clearly demonstrated that both organic and mineral fertilizers
were needed to increase crop production, improve NUE and maintain soil fertility level. 相似文献