Evaluation of Agricultural Production Systems Simulator (APSIM) as yield predictor of Panicum virgatum and Miscanthus x giganteus in several US environments

Simulation models for perennial energy crops such as switchgrass (Panicum virgatum L.) and Miscanthus (Miscanthus x giganteus) can be useful tools to design management strategies for biomass productivity improvement in US environments. The Agricultural Production Systems Simulator (APSIM) is a biophysical model with the potential to simulate the growth of perennial crops. APSIM crop modules do not exist for switchgrass and Miscanthus, however, re‐parameterization of existing APSIM modules could be used to simulate the growth of these perennials. Our aim was to evaluate the ability of APSIM to predict the dry matter (DM) yield of switchgrass and Miscanthus at several US locations. The Lucerne (for switchgrass) and Sugarcane (for Miscanthus) APSIM modules were calibrated using data from four locations in Indiana. A sensitivity analysis informed the relative impact of changes in plant and soil parameters of APSIM Lucerne and APSIM Sugarcane modules. An independent dataset of switchgrass and Miscanthus DM yields from several US environments was used to validate these re‐parameterized APSIM modules. The re‐parameterized modules simulated DM yields of switchgrass [0.95 for CCC (concordance correlation coefficient) and 0 for SB (bias of the simulation from the measurement)] and Miscanthus (0.65 and 0% for CCC and SB, respectively) accurately at most locations with the exception of switchgrass at southern US sites (0.01 for CCC and 2% for SB). Therefore, the APSIM model is a promising tool for simulating DM yields for switchgrass and Miscanthus while accounting for environmental variability. Given our study was strictly based on APSIM calibrations at Indiana locations, additional research using more extensive calibration data may enhance APSIM robustness.Fil: Ojeda, Jonathan Jesus. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Entre Ríos. Facultad de Ciencias Agropecuarias; ArgentinaFil: Volenec, Jeffrey J.. Purdue University; Estados UnidosFil: Brouder, Sylvie M.. Purdue University; Estados UnidosFil: Caviglia, Octavio Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Entre Ríos. Facultad de Ciencias Agropecuarias; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Entre Ríos. Estación Experimental Agropecuaria Paraná; ArgentinaFil: Agnusdei, Mónica G.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentin

Crop Responses to AmiSorb in the North Central Region

Originally used to prevent scale in boilers, carpramid or thermal polyaspartate (copoly[(3-carboxypropionamide)( 2-carboxylmethyl) acetamide)] was brought to agriculture under the trade names AmiSorb and Magnet. It claimed to increase nutrient uptake through artificially increasing the volume of soil occupied by roots through increased root branching and root hair development. Under controlled hydroponic or greenhouse conditions, the use of carpramid increased nutrient uptake, some yield determining factors such as wheat tillering and in some cases, crop yield. Extensive field testing from 1996 to 1998 under various nutrient regimes, placements, forms, and timings resulted in very inconsistent performance. Averaged across all experiments for which data were available, small yield increases were observed for corn (+1.75 bushels/acre), soybean (+0.63 bushel/acre), wheat (+1.07 bushels/acre), and grain sorghum (+0.32 bushel/acre), but at best only about one-fourth of the experiments (27 percent for corn and wheat) showed statistically significant yield increases. Across all crops, only three experiments showed an economic advantage to using carpramid. An attempt was made to better define the conditions when responses were observed but no clear pattern emerged that would allow improved probability of predicting a positive response.https://lib.dr.iastate.edu/extension_pubs/1225/thumbnail.jp

Robust spatial frameworks for leveraging research on sustainable crop intensification

Meeting demand for food, fiber, feed, and fuel in a world with 9.7 billion people by 2050 without negative environmental impact is the greatest scientific challenge facing humanity. We hypothesize that this challenge can only be met with current and emerging technologies if guided by proactive use of a broad array of relevant data and geospatial scaling approaches to ensure local to global relevance for setting research priorities and implementing agricultural systems responsive to real-time status of weather, soils, crops, and markets. Despite increasing availability of field-scale agricultural data, robust spatial frameworks are lacking to convert these data into actionable knowledge. This commentary article highlights this knowledge gap and calls attention to the need for developing robust spatial frameworks that allow appropriate scaling to larger spatial domains by discussing a recently developed example of a data-driven strategy for estimating yield gaps of agricultural systems. To fully leverage research on sustainable intensification of cropping systems and inform policy development at different scales, we call for new approaches combining the strengths of top-down and bottom-up approaches which will require coordinated efforts between field scientists, crop modelers, and geospatial researchers at an unprecedented level

Agricultural Impacts of Climate Change in Indiana and Potential Adaptations

While all sectors of the economy can be impacted by climate variability and change, the agricultural sector is arguably the most tightly coupled to climate where changes in precipitation and temperature directly control plant growth and yield, as well as livestock production. This paper analyzes the direct and cascading effects of temperature, precipitation, and carbon dioxide (CO2) on agronomic and horticultural crops, and livestock production in Indiana through 2100. Due to increased frequency of drought and heat stress, models predict that the yield of contemporary corn and soybean varieties will decline by 8–21% relative to yield potential, without considering CO2 enhancement, which may offset soybean losses. These losses could be partially compensated by adaptation measures such as changes in cropping systems, planting date, crop genetics, soil health, and providing additional water through supplemental irrigation or drainage management. Changes in winter conditions will pose a threat to some perennial crops, including tree and fruit crops, while shifts in the USDA Hardiness Zone will expand the area suitable for some fruits. Heat stress poses a major challenge to livestock production, with decreased feed intake expected with temperatures exceeding 29 °C over 100 days per year by the end of the century. Overall, continued production of commodity crops, horticultural crops, and livestock in Indiana is expected to continue with adaptations in management practice, cultivar or species composition, or crop rotation

Indiana’s Agriculture in a Changing Climate: A Report from the Indiana Climate Change Impacts Assessment

Indiana has long been one of the nation’s leaders in agricultural productivity. Favorable temperatures and precipitation help Indiana farmers generate over $31 billion worth of sales per year, making the state 11th in total agricultural products sold. Changes to the state’s climate over the coming decades, including increasing temperatures, changes in precipitation amounts and patterns, and rising levels of carbon dioxide (CO2) in the air will result in several direct and indirect impacts to the state’s agricultural industry. This report from the Indiana Climate Change Impacts Assessment (IN CCIA) describes how projected changes in the state’s climate will affect the health of livestock and poultry, growing season conditions for crops, the types of crops that can be planted, soil health and water quality as well as weed, pest and disease pressure for agricultural production statewide

Determinants of potassium acquisition by cotton (Gossypium hirsutum L.) from a vermiculitic soil.

Includes "Root development of two cotton cultivars in relation to potassium uptake and plant growth in a vermiculitic soil," by S.M. Brouder and K.G. Cassman, reprinted from Field Crops Research, 1990, v.23, pp.187-203.Degree granted in Ecology.Typescript.SPEC. COLL. HAS ARCHIVAL COPY; MICRO. ROOM HAS MICROFICHE COPY (2 SHEETS).Thesis (Ph.D.)--U. of Calif., Davis.Mode of access: Internet

The impact of conservation agriculture on smallholder agricultural yields: A scoping review of the evidence

Widespread implementation of conservation agriculture (CA) in North and South America and Australia suggests significant farmer profitability achieved through some combination of sustained or increased agronomic productivity and reduced input costs. Many believe similar agronomic benefits can accrue to smallholder farmers in sub-Saharan Africa (SSA) and South Asia (SA) for a broad array of crops and farming systems despite marked differences in biophysical and socio-economic environments across these regions. Our objectives were to characterize (1) the quality of existing research including an assessment of the relevance of previously published reviews and surveys to SSA and SA, and (2) the empirical evidence from SSA and SA for agronomic benefits derived from implementing zero tillage (ZT) including the identification of knowledge gaps. Mulching and rotation were considered as associated practices within systems. Among surveys and reviews, most syntheses of multiple, independent studies were either entirely qualitative or used overly simplistic approaches to data aggregation. Few reviews used meta-analysis or other rigorous statistics that permit assessment of outcome sensitivity to influential observations; in general, review protocol descriptions were not sufficient to ensure transparency and appropriate handling of common biases. A search and screening of peer-reviewed literature identified empirical studies on conservation tillage in SSA and SA for maize (22), rice (16), cowpea (10) and sorghum (8). In attempting to extract data for an unbiased, systematic review of CA and maize, we found few studies fully reported critical data or meta-data; most common omissions were the univariate statistics required for study use in meta-analyses and critical supporting or explanatory data on soil type, prevailing weather, and management practices including handling of crop residues. In the short-term, ZT generally resulted in lower yields than with conventional tillage (CT). Occasionally these reductions could be linked to direct effects (e.g. increased soil compaction in rice), but failure to adapt other managements (e.g. weed control) to the CA system was a common and confounding indirect effect. Sufficient maize data existed to demonstrate that negative impacts on yield ameliorated with time in some cases accompanied by higher soil water infiltration and soil organic matter, particularly when mulch was added. However, the low number of studies, the missing supporting data and the large variation in treatments made it difficult to infer general direct effects due to mulching or rotation.Well-designed long-term experiments on CA featuring sound agronomic practice and comprehensive documentation are largely missing from the literature. Future systematic reviews addressing agronomic impacts of CA interventions will require appropriate handling of within and between study variance as well as sensitivity analyses and quantitative assessments of publication bias; on-going and future empirical studies must report a minimum dataset encompassing valid statistical measures and comprehensive intervention descriptions that enable standardization and systematic approaches in syntheses. We propose a minimum dataset that is generic to competent agronomy with measurements that are increasingly low-cost and easy to achieve and should therefore be routine in field experiments quantifying and explaining crop and cropping system performance. Until a larger number of field studies provide such quantifying and explanatory data from key crops and representative cropping systems, it is not possible to make strong general conclusions about benefits of CA and ZT on yields and resource use efficiency of smallholder farmers. © 2013 Elsevier B.V.Peer Reviewe