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(a) Geographic information System (GiS) shapes at different distances from buffers in contour grass strip (cGS) and agroforestry (AGF) watersheds used for yield extractions from corn and soybean georeferenced yield maps during the study years at the paired watershed study, Greenley research center, Missouri. (b) inset map shows the selected area within each watershed. Grass bu in the legend indicates the strips in cGS watershed used for yield extraction at different distances from cGS buffers. Similarly Agrof bu in the legend indicates the strip in AGF watershed used for yield extraction at different distances from AGF buffers.
Source publication
Contour perennial buffers within cropland reduce pollutants from watersheds, but may interfere and affect crop yields at the crop-buffer interface. The objective of this study was to evaluate the temporal and spatial effects of agroforestry (AGF) and contour grass (CGS) buffers on no-till corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] yiel...
Context in source publication
Context 1
... soybean (2005, 2007, and 2009) year. The mean yields at representative distances were obtained by extracting yield data points from geo referenced yield data maps (collected by a yield monitor) using selection tools in ArcGIS 9.3 software and GIS shape files created for 0-to 5-m, 5-to 10-m, 10-to 15-m, and 15-to 20-m distances from the buffers (Fig. 2a). The shape files for distances were created using geo-referenced land- use maps of the two ...
Similar publications
Biomass production systems as well as agroforestry and grass buffers have been found to improve soil hydraulic properties and water quality relative to row crop management for temperate regions. Objectives of this study were to assess the effects of biomass crops, agroforestry buffers, and grass buffers grown on claypan soils relative to a traditio...
Agroforestry buffers have recently been introduced in temperate regions to enhance conservation of soil and water resources in row crop management. The effects of agroforestry and grass-legume buffers on in situ water infiltration relative to row crop management (RC) were assessed for a claypan soil in northeastern Missouri, USA. Infiltration rates...
Citations
... Crop yields were comparable to the means for the region during the study. However, the reduction of corn yield was greater than soybeans for the 0-5-m strip from the buffer edge compared to 20-m from the buffer edge (Senaviratne et al 2012). This may indicate competition for resources including nutrients, water, soil volume for roots, and light (Jose et al. 2000;Senaviratne et al 2012;Udawatta et al 2014Udawatta et al , 2016 and utilization of resources including water and nutrients by the trees. ...
... However, the reduction of corn yield was greater than soybeans for the 0-5-m strip from the buffer edge compared to 20-m from the buffer edge (Senaviratne et al 2012). This may indicate competition for resources including nutrients, water, soil volume for roots, and light (Jose et al. 2000;Senaviratne et al 2012;Udawatta et al 2014Udawatta et al , 2016 and utilization of resources including water and nutrients by the trees. ...
... Vol.: (0123456789) The current study showed carbon and biomass accumulation at the site. Several studies conducted at this site have shown numerous benefits including soil hydraulic, lower bulk density, porosity, water quality, biodiversity, soil carbon sequestration, and soil water dynamics (Alagele et al 2020;Sahin et al. 2016;Salceda et al. 2022;Senaviratne et al. 2012Senaviratne et al. , 2013Senaviratne et al. , 2014Senaviratne et al. , 2005Senaviratne et al. , 2011aUdawatta et al. 2022, b). Findings of the current study and other research at the same site show that agroforestry is a strong NbS that can provide numerous ecosystem benefits from the same land parcel while reducing the impact of agriculture on the environment and forests. ...
Trees are intentionally integrated in agroforestry for numerous ecosystem services including carbon sequestration, environmental, production, and economics. Open tree growth is different from that in forests and data is limited, thus restricting integration of trees in agroforestry for optimum benefits. Growth of pin oak (Quercus palustris Muenchh.), swamp white oak (Q. bicolor Willd.), and bur oak (Q. macrocarpa Michx.) were evaluated for 24 years in an alley cropping agroforestry watershed in Northern Missouri, USA. Containerized oak seedlings were planted at 3-m spacing in the center of 4.5-m wide contour grass-legume strips established at 22.8–36.5 m intervals on a 4.44-ha watershed with a corn (Zea mays L.)-soybean (Glycine max (L.) Merr.) rotation. Tree height and diameter (dbh and 10-cm) were recorded. Among the three species pin oak had the greatest height, diameter at 10-cm, and dbh growth during the 24-year study. Pin oak trees showed 1.2-, 1.4-, and 1.2-times greater height, 10-cm diameter, and dbh than swamp white oak trees, the second-best species at the watershed. Biomass and carbon values of pin oak were 1.7 and 3.7 times in 2021 than swamp white oak and bur oak. Bur oak trees had the lowest height, 10-cm diameter, dbh, biomass, and carbon values among the three species. With the 3-species composition, tree biomass and carbon accumulation in a 24-year period were 22,613 and 10,854 kg ha−1. Trees had > 20% tapering in the main stem. Among the three species swamp white oak had 21% tapering while pin and bur oak both had 25% tapering. All three species appear to be suitable for watershed protection while pin oak showed promising growth and greater accumulation of biomass and carbon. The study emphasizes development of agroforestry-specific tree growth models as open-grown trees differ from those in conventional forestry. This can help the selection of suitable species for enhanced ecosystem services
... Anderson et al. (2009) found that watersheds with agroforestry buffer strips in Missouri U.S. had lower soil water content early in the growing season than crop watersheds, but this has not been confirmed within prairie strip fields. Fifth, prairie strips could compete with adjacent crops for nutrients, but this is likely weather-and vegetation-dependent (Banik et al., 2020;Senaviratne et al., 2012), and this, too, has not yet been tested in prairie strip fields. Lastly, prairie strips may positively or negatively alter adjacent crops and soils through mechanism(s) of which we are unaware. ...
... Ghaffarzadeh et al. (1994) found that the maize yield benefitted from soybean intercropping when water stress was low, but when water stress increased, the yield from border maize rows declined. Other studies have shown that perennial vegetation can negatively affect nearby soybean and maize physiology or yields (Banik et al., 2020;Rivest and Vézina, 2015;Senaviratne et al., 2012;Udawatta et al., 2016). Contour grass strips and agroforestry strips, for example, can reduce grain yield by 15-49% in adjacent crops (Senaviratne et al., 2012). ...
... Other studies have shown that perennial vegetation can negatively affect nearby soybean and maize physiology or yields (Banik et al., 2020;Rivest and Vézina, 2015;Senaviratne et al., 2012;Udawatta et al., 2016). Contour grass strips and agroforestry strips, for example, can reduce grain yield by 15-49% in adjacent crops (Senaviratne et al., 2012). Speculation on mechanisms driving these negative responses includes the competition for water (Rivest and Vézina, 2015;Senaviratne et al., 2012) and nutrients, especially nitrate (Banik et al., 2020;Zhou et al., 2010). ...
... In vineyard AGF systems, competition for N can be addressed by planting leguminous cover crops, applying higher rates of fertilizer in vine rows closer to tree rows, or selecting N-fixing trees for intercropping (Nair 1993c, d). Competition for water has been shown to be less of an issue in vineyard agroforestry systems, but during drought years, competition for water can be addressed through management practices such as root pruning, branch pruning, and tree thinning (Peter and Lehmann 2000;Reynolds et al. 2007;Dupraz et al. 2009;Senaviratne et al. 2012;Trambouze et al. 2017;Grimaldi 2018). Competition for both water and N can be addressed by combining vines with tree species whose roots occupy different soil niches than grapevine roots, or by spacing trees more widely (Nair 1993e). ...
In the face of climate change and environmental degradation, modern viticulture risks the threats of reduced soil fertility, increased heat stress, water scarcity, extreme climate events, and increased pest and disease pressure. Agroforestry (AGF) is a sustainable land-use system proven to address many of these conservation and production issues, and yet, agroforestry’s applications in viticulture have been severely overlooked. This review uses published peer-reviewed literature, as well as some gray literature, to summarize the current knowledge surrounding the belowground interactions between trees and grapevines and their effects on water availability, nutrient availability, and grapevine rooting patterns in vineyard AGF systems, so as to better understand how AGF can help address the issues currently facing modern viticulture. Existing studies reveal that the presence of trees in vineyards may impart a neutral to positive effect on parameters surrounding grapevine water status and stress despite competition, due to trees’ ability to reduce evaporation and transpiration, modify the microclimate, and distribute water through hydraulic lift. Studies show that trees may have a slightly negative effect on grapevine nutrient status within 4 m of trees; however, trees have also been proven to significantly improve vineyard soil quality. Trees may also potentially increase vine rooting depth and density by improving soil structure and inducing root plasticity. Overall, the incorporation of trees in vineyards can create more resilient agroecosystems, can improve certain grape quality and production parameters, can increase farmer savings, and can better the environment in numerous ways. More studies on tree/vine belowground interactions are needed, especially ones that examine different tree/vine species combinations, grape trellis systems, row orientations, and growing zones. However, existing evidence, as summarized in this review, indicates that AGF has great potential applications in viticulture despite trade-offs, especially in the face of extreme temperatures, pests, plagues, and weather events that are predicted to occur in the coming years.
... It is apparent that in the early stage of growing season 1, the soil mo isture was significantly low co mpared to the latter stage as shown in Fig.8.a while the reverse trend is evident for growing season 2 as indicated in Fig.8.b. In addition, the soil mo isture exhibit less variation in growing season 2 compared to that of growing season 1. Inadequate soil moisture leads to slow germination, sluggish growth rate, smaller leaf area, lesser number of pods per plant, reduced number of seeds per pod, and ultimately reduced crop yield [14]. Th is is because low water amount in the soil results to not only low bio mass formation but also lower biological nitrogen fixation [15]. ...
... These are the same five models used by Baffaut et al. (2017) to evaluate an uncalibrated best professional judgement (BPJ) model parameterization. The general watershed characteristics, data collection, and methods of calibration and validation are described in papers within this special issue Bhandari et al., 2017) and in previously published works Senaviratne et al., 2012Senaviratne et al., , 2013Senaviratne et al., , 2014. Calibration of each SSCM started with the BPJ control file options and parameters and resulted in five SSCMs that differed from the BPJ parameterization for three options in the control file (Supplemental Table S2) and 21 values in the parameter file (Supplemental Table S3). ...
Phosphorus (P) Index assessment requires independent estimates of long‐term average annual P loss from fields, representing multiple climatic scenarios, management practices, and landscape positions. Because currently available measured data are insufficient to evaluate P Index performance, calibrated and validated process‐based models have been proposed as tools to generate the required data. The objectives of this research were to develop a regional parameterization for the Agricultural Policy Environmental eXtender (APEX) model to estimate edge‐of‐field runoff, sediment, and P losses in restricted‐layer soils of Missouri and Kansas and to assess the performance of this parameterization using monitoring data from multiple sites in this region. Five site‐specific calibrated models (SSCM) from within the region were used to develop a regionally calibrated model (RCM), which was further calibrated and validated with measured data. Performance of the RCM was similar to that of the SSCMs for runoff simulation and had Nash–Sutcliffe efficiency (NSE) > 0.72 and absolute percent bias (|PBIAS|) < 18% for both calibration and validation. The RCM could not simulate sediment loss (NSE < 0, |PBIAS| > 90%) and was particularly ineffective at simulating sediment loss from locations with small sediment loads. The RCM had acceptable performance for simulation of total P loss (NSE > 0.74, |PBIAS| < 30%) but underperformed the SSCMs. Total P‐loss estimates should be used with caution due to poor simulation of sediment loss. Although we did not attain our goal of a robust regional parameterization of APEX for estimating sediment and total P losses, runoff estimates with the RCM were acceptable for P Index evaluation.
Core Ideas
Regionally calibrated APEX produced very good estimates of site‐specific runoff.
Regionally calibrated APEX failed to adequately estimate sediment loss.
Regionally calibrated APEX P‐loss estimates were worse than site‐specific models.
APEX runoff estimates are adequate for rigorous evaluation of P Index runoff components.
APEX sediment loss estimates are unsuitable for evaluation of P Index.
... HRcrop yield Of the 951 studies identified through database searching, 28 were retained based on title and abstract. Of these 28 studies, the following were used in the analyses: Rivest and Vézina (2014), Burgess et al. (2005), Chirko et al. (1996), Gao et al. (2013), Reynolds et al. (2007), Senaviratne et al. (2012), Woodall and Ward (2002). After reference checking and author searching, Stamps et al. (2009) Leguédois et al. (2008). ...
In north western Europe, agricultural systems are generally managed to maximize the potential delivery of provisioning ecosystem services. This has often been at the expense of other ecosystem services. Because the current supply of most ecosystem services is insufficient to meet the increasing demand, particular attention to ecosystem service delivery and hence multifunctionality in agriculture is vital. In this paper, we quantitatively assessed the impact of hedgerows and grass strips bordering parcels with annual arable crops on the simultaneous delivery of a set of ecosystem services and from there we identified synergies and trade-offs on virtual parcels. After a systematic literature search, mixed models were applied on observations from 60 studies and quantitative effect relationships between ecosystem service delivery and hedgerow and grass strip characteristics were developed. Next to the hedgerow, until a distance of twice the hedgerow height, arable crop yield was reduced by 29%. Beyond this distance, until 20 times the hedgerow height, crop yield was increased by 6%. Compared to a similar arable parcel without hedgerow or grass strip, soil carbon stock was 22% higher in the hedgerow, on average 6% higher in the adjacent parcel next to the hedgerow and 37% higher in the upper 30 cm soil layer in the grass strip. Both hedgerows and grass strips intercepted nitrogen from the surface (69% and 67%, respectively) and subsurface (34% and 32%, respectively) flow and phosphorus (67% and 73%, respectively) and soil sediment (91% and 90%, respectively) from the surface flow. More natural predator species were found on parcels with hedgerows, but the number of predators was unaffected. On parcels with grass strips, both predator density and diversity was higher and aphid density was reduced. Our calculations on parcel level indicate that the trade-off between arable crop yield and regulating ecosystem services depends on hedgerow width and height and parcel dimensions. A similar trade-off is found on parcels with grass strips, but increasing grass strip width results in a proportionally higher delivery of regulating ecosystem services.
... In 2006, corn was planted and harvested over both the AGF and CGS areas on 14 April and 27 September respectively, with a mean yield of 11.06 Mg ha −1 . In 2007, soybeans were seeded on both the AGF and CGS areas at 444,600 seeds ha −1 on 8 June and harvested on 26 October with a mean yield of 3.4 Mg ha −1 (Senaviratne et al., 2012). ...
Improved soil and water quality, and carbon sequestration are notable benefits of agroforestry practices compared to row-crop agriculture. Over an agricultural watershed with two buffer cropping systems (agroforestry buffers and grass buffers) soybean crop evapotranspiration was calculated from the Penman-Monteith equation using 10-min averages of meteorological measurements within crop alleys for 54 days in summer 2007. Wind speeds were consistently lower over the agroforestry buffer portion of the watershed by an average of 0.42 m s−1. For calculated evapotranspiration assuming water-stressed conditions, this decrease in wind speed from the presence of agroforestry buffers was offset almost entirely by an increase in net radiation. Net radiation differences between the two systems were highest during the morning (∼40 W m−2) and were likely the result of solar radiation scattered from the agroforestry buffers. Wind speed reduction over the crop portion surrounded by agroforestry buffers varied by wind direction with daytime winds ≥0.6 m s−1 greater over the grass buffer portion of the crop for northerly and southerly winds (nearly perpendicular to the agroforestry buffers). Therefore, buffer orientation relative to the prevailing wind is important for reducing evapotranspiration. Changes in crop alley width would be expected to impact the portion of the crop within wind-sheltered zones and the portion receiving scattered radiation from trees. The sensitivity of evapotranspiration to agroforestry buffer orientation and crop alley width should be a focus of future investigations.
... The buffer also needs to be perpendicular to the wind direction or the runoff slope to realize the maximum benefits. Benefits of buffer strips include improved microclimate, water conservation, and soil protection, which improve growing conditions (Bang et al. 2010;Cleugh et al. 1998) and increase crop yield (Senaviratne et al. 2012). Wind barrier research under irrigated conditions is limited. ...
... Thus it will realize most of the benefits regardless of wind direction or slope. Similarly, planting grass or tree buffer strips on contours or across the slope to minimize water erosion have shown promise (Senaviratne et al. 2012). When the direction of the resource or pollutant movement is known, building a barrier across it will reduce the loss of that resource or pollutant. ...
Excerpt
Life on Earth, including that of humans, depends entirely on ecosystem services. In spite of that, in the last 50 to 60 years, human activities have degraded ecosystems more rapidly than in any comparable time in human history (MEA 2005). This is happening at a time when the global population is rapidly increasing to reach nine billion and other drivers, like climate change, overexploitation and pollution of natural resources, and economic growth, are also increasing (Carpenter 2009). Therefore, innovative ideas are needed to improve ecosystem services while increasing food production.
Irrigation from the Ogallala Aquifer has converted the southern Great Plains (SGP) from a dust bowl to a highly productive agricultural region. Water from the aquifer is used to irrigate over 2.6 × 10⁶ ha (6.5 × 10⁶ ac) in the SGP and has supported a flourishing rural economy that includes large beef and dairy industries. The water level of the aquifer is gradually decreasing because extraction exceeds recharge. In extreme cases, the water level has declined up to 84 m (277 ft) below predevelopment levels (McGuire 2007). Because of overexploitation of the Ogallala Aquifer, 35% of the irrigated acreage is expected to be rainfed in a few decades (Scanlon…
... Muth (2014) provided a vision for developing a sustainable farm plan to improve profits using practices such as RB and CRP or alternative crops in areas of lower soil productivity and environmentally sensitive areas. In addition, conservation practices such as RB and CRP lands are widely promoted and numerous studies have evaluated their environmental benefits, but only a few studies have examined long-term effects on crop yields with these practices (Senaviratne et al., 2012;Udawatta et al., 2014). Information for RB and CRP effects with yearly weather and distance from buffer when growing corn and soybean is limited. ...
... In 2010, these same two comparisons showed reductions of 52 and 67%. Alley cropping buffer studies in Missouri showed 15 to 90% grain yield reductions with 6and 22-yr-old tree buffers (Senaviratne et al., 2012;Udawatta et al., 2014). They attributed reductions to competition for moisture and light. ...
... Crop yield was not affected by trees growth during the first 4 yr but as trees grew, yield reductions were significant (Lott et al., 2000). Senaviratne et al. (2012) also showed a progressive yield decline from the tree buffer with time for the younger alley cropping system. Yield reductions observed in the current study were similar to those findings. ...
Riparian buffers (RB) and the Conservation Reserve Program (CRP) can improve water and soil quality. However, these practices can reduce crop yields, especially at the tree/CRP‐crop interface. The objective of this study was to quantify yield differences in a no‐till corn ( Zea mays L.)–soybean [ Glycine max (L.) Merr.] rotation with a multi‐species RB, CRP, and riparian with root pruning (RRP). Crop yields were determined in triplicate plots by rows from 2007 to 2010. Regression analysis was used to evaluate yield differences among years and distances from the tree/CRP‐crop interface and RRP. Corn yield at 0.76‐m was 97, 97, 65, and 66% lower than the yield at 9‐m away from the interface in 2007, 2008, 2009, and 2010, respectively for RB. Averaged across 4 yr corn yields at 0.76 m was 61, 74, and 81% of that at 3, 6, and 9 m. The CRP had no effect on corn yields. Effects of RB and CRP were not significant for soybean. The RRP showed increasing yield for rows from the tree interface for corn and soybean. The distance explained 21 to 60% and 15 to 52% of the yield variations in corn and soybean, respectively, with the RRP treatment. Results are applicable only to the studied distances. Results of the study suggest selection of a less sensitive crop such as soybean for use with RB in the first 9 m (12 rows), or use of CRP to generate additional income and ecosystem services to offset any loss in grain.
Core Ideas This manuscript evaluated riparian buffer, CRP, and riparian with root pruning on corn and soybean yields for 4 years.
Riparian with root pruning significantly reduced crop yields near the buffer/crop border. The CRP effect was not significant.
Results of the study imply the importance of land management practices for production and environmental benefits.
... Tree roots are known to partition soil water in two ways; temporally through seasonal displacement of leaves which controls transpirational water loss (Liang et al. 2011) and spatially through partitioning of roots to different active layers and horizontal spacing (Burgess et al. 2000;Tang et al. 2001;Isaac et al. 2014;Schwendenmann et al. 2015). Many studies draw conclusions on water acquisition based on inferences related to soil moisture content and performance metrics, although the mechanisms are unclear (Jose et al. 2000;Miller and Pallardy 2001;Wanvestraut et al. 2004;Senaviratne et al. 2012). ...
Tree-based intercropping (TBI) systems induce microclimate modifications that can enhance crop performance through water use efficiency. However, the extent of this efficiency is dependent on water acquisition strategies of trees in such agroforestry systems. Charting water uptake zones at the tree-crop root interface in TBI systems is essential for managing water resources, particularly with increasing water stress from a changing climate. In this study, we identify the water uptake zones of Juglans nigra (walnut) and Populus sp. (hybrid of Populus deltoids X Populus nigra clone DN-177) (poplar) intercropped with winter barley (Hordeum vulgare) in a temperate TBI system. Water isotopic analysis using δ18O was conducted on paired soil water and tree xylem water samples in early season (pre-crop) and late season (with crop) collected from the Agroforestry Research Station in Guelph, Ontario, Canada. Two approaches for identifying the water uptake zones were used: direct inference and multiple source mass-balance analysis. Both approaches showed that poplar exhibits a dominant soil water uptake zone at 20 cm in the soil profile in the early season, while the dominant walnut uptake zone was higher in the soil profile at 10 cm. Depth of water uptake was lower in the soil profile (40-70 cm) in the late season for both species. This study indicates: (i) tree species dependent water acquisition zones, and (ii) a shift in tree water acquisition to deeper in the soil profile over the growing season. Using isotopic techniques, we suggest that poplar and walnut root activity stratify below the crop root zone later in the growing season, potentially reducing competition for water resources.
