- Authors:
- Feng, G.
- Sharratt, B.
- Young, F.
- Source: Journal of Soil and Water Conservation
- Volume: 66
- Issue: 4
- Year: 2011
- Summary: In the low precipitation zone (<0.3 m [11.8 in] annual precipitation) of the Inland Pacific Northwest, no-tillage continuous spring cereal and no-tillage spring cereal-chemical fallow rotations are being examined as alternatives to the traditional winter wheat-summer fallow rotation for soil conservation. There is limited information, however, regarding the long-term effects of no-tillage cropping systems on soil hydraulic properties in this semiarid region. The objective of this study was therefore to characterize infiltration, water retention, saturated hydraulic conductivity and bulk density of a silt loam that had been subject to various tillage and crop rotations in east-central Washington. Treatments examined included no-tillage spring barley-spring wheat (NTSB-SW), no-tillage spring wheat-chemical fallow (NTSW-ChF), and traditional winter wheat-summer fallow (WW-SF). Soil properties were measured in spring and late summer 2006 due to the vulnerability of the soil to rapidly dry and erode during these seasons. Saturated hydraulic conductivity was determined by the falling-head method, infiltration was measured using a double-ring infiltrometer, and water retention characteristics was assessed by examining the temporal variation of in situ soil water content. NTSB-SW resulted in higher infiltration and saturated hydraulic conductivity, lower bulk density, and larger and/or more continuous pores in the upper soil profile (<0.1 in [<3.9 in] depth) than WW-SF and NTSW-ChE Infiltration and saturated hydraulic conductivity were lower for chemical fallow than for traditional fallow in spring whereas hydraulic conductivity was lower for summer fallow than chemical fallow in late summer. Soil hydrologic properties appeared more favorable for no-tillage continuous spring cereal rotations. These results arc useful for soil and water management and conservation planning in the low precipitation zone of the Inland Pacific Northwest.
- Authors:
- Fernandez, M. R.
- Ulrich, D.
- Brandt, S. A.
- Zentner, R. P.
- Wang, H.
- Thomas, A. G.
- Olfert, O.
- Source: Agronomy Journal
- Volume: 103
- Issue: 3
- Year: 2011
- Summary: The impact of cropping system management on root and crown rot of spring wheat ( Triticum aestivum L.) was examined on a Dark Brown Chernozem (Typic Boroll) soil in the Canadian Prairies. This systems approach tried to reflect the most common practices of organic and conventional producers in this region. The study consisted of a factorial combination of three input levels (high, with tillage, fertilizer and pesticides; reduced [RED], with conservation tillage, targeted fertilizer and weed control; and organic [ORG] with tillage and N-fixing legumes); and three levels of cropping diversity (low diversity with wheat and summerfallow or legume green manure fallow; diversified using annual grain crops; and diversified using annual grain crops and perennial forages). All rotations were 6 yr long. Subcrown internodes and crowns/lower culms of wheat plants were scored for discoloration, and fungi in discolored tissue were identified and quantified. Overall, input level had a greater impact on disease levels and fungal frequency than cropping diversity. Discoloration severity was lowest in the RED systems, which was attributed to lower percentage isolation of Cochliobolus sativus, the most common pathogen. Fusarium species varied with input level. The pathogens F. avenaceum and F. culmorum were most associated with RED and/or least associated with ORG systems, whereas the weak pathogen/saprophyte F. equiseti was most associated with ORG systems. Thus, ORG management helped to reduce populations of F. avenaceum and F. culmorum, two of the most important Fusarium pathogens in the Canadian Prairies.
- Authors:
- Fisher, K. A.
- Momen, B.
- Kratochvil, R. J.
- Source: Agronomy Journal
- Volume: 103
- Issue: 2
- Year: 2011
- Summary: Agricultural nutrient runoff to the Chesapeake Bay has been under intense scrutiny for more than a decade in Maryland. One method for capturing these nutrients, especially N, is the use of winter cover crops. This study compared various broadcast cover crop treatments with and without soil incorporation to planting winter cover crop seed with a no-till drill. Seedling emergence and N uptake were the dependent variables measured for two planting dates and seven planting methods. The effects of planting date and planting method for winter wheat ( Triticum aestivum L.) and cereal rye ( Secale cereale L.) following corn ( Zea mays L.) harvest were investigated at two locations. The study was conducted over two winter cover crop growing seasons: 2007-2008 and 2008-2009. Treatments that incorporated the seed into the soil consistently established better stands of cover crops and took up more N regardless of fluctuations in temperature, rainfall, and planting date. Early planted cover crops consistently took up more N than those planted on the later planting date. Performance of the broadcast treatments was highly dependent on rainfall and mild temperatures for success, but did take up notable amounts of N when planted early under good growing conditions. The few differences that were found in the N uptake between wheat and rye within the same planting treatment always indicated that the rye achieved better N uptake than wheat.
- Authors:
- Flower, K. C.
- Crabtree, W. L.
- Source: Field Crops Research
- Volume: 121
- Issue: 1
- Year: 2011
- Summary: On acid soils, no-tillage farmers are often advised to apply lime to the soil surface without incorporation by tillage. As such, it can take a number of years before the subsoil acidity is decreased. However, no-tillage seeders vary in the level of soil disturbance caused during seed placement. The consequence of such variations in soil disturbance for the effectiveness of lime in no-tillage cropping has not been explored. Our objectives were (i) to determine if the liming effect could be accelerated by increasing the rate of lime and level of soil disturbance during no-tillage seeding, and (ii) evaluate the effect of no-tillage seeding method, rate of lime and soil pH on yield of wheat, barley, canola and lupins. Three trials, each with a factorial design consisting of four seeding methods and four lime rates, were established in 1999 and continued until 2005. The soil had a texture contrast with about 15-20 cm of sand over yellow sandy clay loam and the initial pH (CaCl 2) at both 0-10 and 10-20 cm was between 4.5 and 4.7. The four seeding treatments were: low disturbance zero-till disc openers (ZT), higher disturbance no-tillage tines with narrow knife-points (NT), higher disturbance full cut seeding with sweeps (FC) for the first three years followed by ZT from then on, and FC for the first year followed by NT thereafter. The four lime rates were 0, 1, 2 and 4 t ha -1. The liming effect was more rapid with the higher disturbance seeding of NT, FCZT and FCNT, compared with ZT; the seeding effect on soil pH diminished with time and was not detected in the subsoil after four years. Higher rates of lime increased this effect and there was no interaction between seeding method and lime rate. This indicated that soil pH under the different seeding methods responded in a similar manner to increased lime. Nonetheless, significant positive linear regressions were found between yield and soil pH for wheat and barley and a negative relationship for lupins. Canola showed no response to soil pH, possibly because establishment was affected by seeding method, and soil pH was not low enough to elicit a response. The ZT seeding method gave lower yields than the other methods for canola and lupins in some years, but had no effect on wheat and barley yields. Higher disturbance at the time of no-till seeding can, therefore, accelerate the liming effect, making earlier economic gains possible.
- Authors:
- Li, Mei
- Gao, XingXiang
- Guo, Xiao
- Sun, TingLin
- Zhao, Wei
- Gao, ZongJun
- Source: Acta Prataculturae Sinica
- Volume: 20
- Issue: 1
- Year: 2011
- Summary: The effects of rotary tillage with no stubble (RT), rotary tillage with straw incorporation (RTS), no-till without stubble (NT), no-till with 6 000 kg/ha (NTS 6000), and no-till with 3 000 kg/ha (NTS 3000), on weed communities structure and species diversity was studied in field experiments using a community ecology method. Compared with RT, the NT, NTS 3000, and NTS 6000 treatments increased perennial weed species, but there was no significant difference in the species richness. NT, NTS 3000 and NTS 6000 significantly reduced the summed dominance ratio (SDR) of Lithospermum arvense, but increased the SDR of Capsella bursa-pastoris. RTS significantly reduced the SDR of L. arvense, but increased the SDR of Descurainia sophia. The species diversity of weed communities varied significantly between different tillage systems. The Bray-Curtis index and hierarchical cluster analysis classified the weed communities of different tillage systems into two categories: Category I (NT, NTS 6000 and NTS 3000) where no-till was implemented, and category II (RTS and RT) where rotary tillage was implemented. The species richness of category I was a little larger than that of category II, but the species diversity and community evenness were much larger than those of category II. However, the community dominance of category I was significantly smaller than that of category II.
- Authors:
- Rickman, R. W.
- Liang, Y.
- Albrecht, S. L.
- Machado, S.
- Kang, S.
- Gollany, H. T.
- Source: Agronomy Journal
- Volume: 103
- Issue: 1
- Year: 2011
- Summary: Long-term field experiments (LTE) are ideal for predicting the influence of agricultural management on soil organic carbon (SOC) dynamics and examining biofuel crop residue removal policy questions. Our objectives were (i) to simulate SOC dynamics in LTE soils under various climates, crop rotations, fertilizer or organic amendments, and crop residue managements using the CQESTR model and (ii) to predict the potential of no-tillage (NT) management to maintain SOC stocks while removing crop residue. Classical LTEs at Champaign, IL (1876), Columbia, MO (1888), Lethbridge, AB (1911), Breton, AB (1930), and Pendleton, OR (1931) were selected for their documented history of management practice and periodic soil organic matter (SOM) measurements. Management practices ranged from monoculture to 2- or 3-yr crop rotations, manure, no fertilizer or fertilizer additions, and crop residue returned, burned, or harvested. Measured and CQESTR predicted SOC stocks under diverse agronomic practices, mean annual temperature (2.1-19 degrees C), precipitation (402-973 mm), and SOC (5.89-33.58 g SOC kg(-1)) at the LTE sites were significantly related (r(2) = 0.94, n = 186, P < 0.0001) with a slope not significantly different than 1. The simulation results indicated that the quantities of crop residue that can be sustainably harvested without jeopardizing SOC stocks were influenced by initial SOC stocks, crop rotation intensity, tillage practices, crop yield, and climate. Manure or a cover crop/intensified crop rotation under NT are options to mitigate loss of crop residue C, as using fertilizer alone is insufficient to overcome residue removal impact on SOC stocks.
- Authors:
- Grebennikov, V.
- Shipilov, I.
- Kushch, E.
- Source: Kormoproizvodstvo
- Issue: 2
- Year: 2011
- Summary: Impacts of perennial legume-grass mixtures on regulation of soil fertility processes were studied in the Stavropol region, Russia in 2006-09. The mixtures consisted of wheat grass, sainfoin, melilot, alfalfa and bluegrass. Growth and development of roots, above-ground biomass and accumulation of organic compounds in soil were measured during the experiment. The total biomass yield of the 5-component mixture reached 9.62 t/ha at the end of the fourth year. Authors recommend this mixture for phytomelioration. The detailed data on yield dynamics of legume-grass mixtures are presented in 2 tables.
- Authors:
- Gruber, S.
- Möhring, J.
- Claupein, W.
- Source: Soil & Tillage Research
- Volume: 115
- Year: 2011
- Summary: Ten years of a long-term field experiment using different strategies of conventional and conservation tillage in SW Germany were evaluated for soil mineral nitrogen (SMN) and soil moisture content. Treatments analysed were combinations of stubble tillage (S) or no stubble tillage with primary tillage P: mouldboard plough, CP: chisel plough, RTT: rototiller, NT: no-till, and VAR: alternating SIP or S/CP. Best management practices were used for crop rotation, fertilisation and plant protection. CP, VAR and NT resulted in 18.7-19.0% gravimetric water content in spring. Partially significantly lower water content was observed in spring under S/P and CP with 18.2%; P and S/RTT resulted in 18.5%. Autumn soil moisture ranged from 15.3 to 15.8% and did not significantly differ between the treatments. Interactions between treatment and depth were not significant. There was no clear trend for spring soil moisture. No treatment showed a particular response to dry or wet season. Total SMN ranged between 8 and 49 kg ha(-1) in spring and 5-26 kg ha(-1) in autumn; significant effects of the treatments or interactions of treatment x depth did not occur. The effect of the season was most relevant for the amount of SMN, probably as a result of different conditions for mineralisation. Downward movement of nitrogen in spring was low in all treatments if catch crops were grown in the previous autumn. Overall, different soil tillage methods had little effect on soil moisture and soil SMN under temperate conditions. Seriously adverse effects of any tillage treatment in terms of nitrate leaching or reduced mineralisation seem unlikely. Similarly, the tillage systems did not exhibit obvious advantages or disadvantages in terms of soil water content. An exception may have been the higher water content in autumn in 0-30 cm under high soil disturbance which provided more suitable conditions for germination of the following crop. The decision of whether or not to adopt conservation tillage in temperate climates seems not to be primarily dependent on soil moisture and nitrogen mineralisation or on nitrogen leaching.
- Authors:
- Gürsoy, S. L.
- Sessiz, A.
- Kiliç, H.
- Bayram, N.
- Source: Archives of Agronomy and Soil Science
- Volume: 57
- Issue: 4
- Year: 2011
- Summary: Soil properties are very important for plant growth and soil conservation. Although soil properties can be influenced by agricultural production systems, this influence has seldom been studied in the semi-arid South East Anatolia region of Turkey. Thus, a three-year experiment was carried out to evaluate the effect of tillage and residue management systems in wheat ( Triticum durum L.) agriculture following cotton ( Gossypium hirsutum L.) on soil properties. A strip plot design with three replications was used, in which two residue management treatments were collecting cotton stalk (SA) and chopping cotton stalk (SB), and six tillage treatments were conventional tillage-I (CT-I), conventional tillage-II (CT-II), vertical tillage (VT), reduced tillage-I (RT-I), reduced tillage-II (RT-II), no-till ridge planting (RP). While there was no difference at 10-20 and 20-30 cm, the penetration resistance was the lowest for CT-I (1.62 MPa) at 0-10 cm. Although tillage treatments had no significant effect on the soil bulk density at 0-10 and 20-30 cm, the lowest bulk density were obtained in RT-II (1.19 g cm -3) at 10-20 cm. Tillage and residue management treatments did not influence the soil organic matter content and pH.
- Authors:
- Source: IOBC/WPRS Bulletin
- Volume: 64
- Year: 2011
- Summary: Slugs are often problems in field crops grown using conservation tillage practices in the eastern United States, as well as certain locations in the Midwest and the southern USA, as well as in Canada. Although most concern has been on corn and soybean, reports of problems from dry beans, cotton, oil-seed rape, sunflowers, winter wheat, and fall planted alfalfa are often received. Although most problems are in fields located in the original forested areas of eastern and southern USA, reports are also being received from the Great Plains' grass lands of slug issues in irrigated no-till fields. Overall, slug problems have increased in geographical area as growers in the USA and Canada have adopted conservation tillage practices. As in other areas of the world, determining new methods of slug control is of utmost importance in order to allow growers to continue using conservation tillage practices. In areas that are new to slugs, a primary concern is educating growers on IPM approaches to slug management.