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Agricultural systems models worldwide are increasingly being used to explore options and solutions for the food security, climate change adaptation and mitigation and carbon trading problem domains. APSIM (Agricultural Production Systems sIMulator) is one such model that continues to be applied and adapted to this challenging research agenda. From its inception twenty years ago, APSIM has evolved into a framework containing many of the key models required to explore changes in agricultural landscapes with capability ranging from simulation of gene expression through to multi-field farms and beyond. Keating et al. (2003) described many of the fundamental attributes of APSIM in detail. Much has changed in the last decade, and the APSIM community has been exploring novel scientific domains and utilising software developments in social media, web and mobile applications to provide simulation tools adapted to new demands. This paper updates the earlier work by Keating et al. (2003) and chronicles the changing external challenges and opportunities being placed on APSIM during the last decade. It also explores and discusses how APSIM has been evolving to a “next generation” framework with improved features and capabilities that allow its use in many diverse topics. [ABSTRACT FROM AUTHOR]

Seasonal fallows – periods with no living plant cover – are frequently implemented in dryland cropping systems to allow recharge of soil moisture for the subsequent cash crop. Over time, repeated fallow periods deplete soil organic matter, a foundation of soil health that affects the long-term functional capacity of soils. Reducing fallow periods by growing cover crops (non-harvested crops terminated prior to reproductive development), double cropping (increasing the frequency of harvested crops), or rotating to ley pasture for several years, were investigated for their potential to improve or maintain soil functional attributes. These 'reduced fallow' systems were compared against a conventional cereal-based production system with seasonal fallows as well as against a permanent fallow. Soil in the reduced fallow systems had higher concentrations of total nitrogen and mineral-associated nitrogen compared with the conventional system and permanent fallow. Reduced fallow systems also had higher concentrations of total organic carbon and mineral-associated carbon than the permanent fallow, but not the conventional system. These changes were associated with greater soil microbial respiration and improved surface soil moisture storage at cash crop planting. The conventional, cover crop and ley pasture systems had similar soil structure with greater abundance of mega-aggregates. In contrast, the double crop system had greater abundance of micro- and macro-aggregates as did the ley pasture systems that were subject to tillage after three years in preparation for a return to cropping. The ley pasture also had substantially greater numbers of root-lesion nematodes (Pratylenchus thornei), surpassing the 2000 nematodes kg-1 threshold for economic damage. The results demonstrate that different methods for reducing fallow periods can generate a range of outcomes that are not uniformly desirable in terms of soil functional attributes. Across the indicators assessed, the cover crop system generated the widest range of improvements in soil fertility and function compared with the conventional system. This suggests cover cropping may be a valuable tool for promoting soil health in subtropical dryland farming systems. • Reduced fallow systems increased SOM, including mineral-associated C and N. • Also increased microbial respiration and topsoil moisture at cash crop planting. • Conventional, cover crop, and ley systems had greatest abundance of mega-aggregates. • Ley pasture had economically damaging numbers of root-lesion nematodes. • Cover cropping may help promote soil health in subtropical dryland farming systems. [ABSTRACT FROM AUTHOR]

• Effect of sowing date on biomass partition varied with forage crop species. • Aboveground biomass at flowering was dependent on rainfall and solar radiation. • Aboveground biomass at maturity more reliant on temperature and rainfall. • Allometric approach should be used in the analysis of allocation pattern. Biomass production and partitioning are important for crop production and is influenced by environmental conditions. Sowing date can profoundly influence biomass production and portioning in crop plants depending upon the local climatic conditions. However, the accumulation of biomass in different plant components in annual forages in response to changes in sowing date has not been quantified, especially for semiarid farming systems. A field experiment was conducted during 2011–2013 to investigate how sowing date (early, mid, late) influences biomass partitioning and the interrelationships with environments in four warm-season annual crops in the Loess Plateau of China. The aboveground biomass of all four crops was more reliant on rainfall and solar radiation at flowering and temperature and rainfall at maturity. Solar radiation, rainfall, and temperature had a combined effect on belowground biomass (0–0.3 m), depending on the forage crop. Reductions in biomass in the late-sown treatment were mostly attributed to plant size; the 'allometry' among plant components did not change. The changes of shoot: root and leaf: stem ratios were related to the relationship between biomass accumulation and rainfall, temperature and intercepted radiation. It is evident that dry matter allocation patterns in crops must be analyzed using a dynamic approach (allometry) and relate with environmental conditions, rather than a static approach using ratios. The results from this study provide references for crop management in forage production and breeding in semiarid areas. [ABSTRACT FROM AUTHOR]

Context: Guidelines recommend palliative care for patients with chronic kidney disease (CKD), who experience a high pain and symptom burden, and receive intensive treatments that often do not align with their values. A lack of scalable specialty palliative care services has prompted calls for attention to primary palliative care, delivered in primary care and nephrology settings., Objectives: The objectives of this study were to 1) describe expectations for care to meet the palliative care needs of people living with CKD, and limitations to meeting those expectations in the current model, and 2) identify potential interventions to meet patients' palliative care needs., Methods: We conducted semi-structured interviews with clinicians from primary care, nephrology, and palliative care to assess 1) reasonable expectations for meeting palliative needs, 2) barriers to integrating primary palliative care, and 3) potential intervention points., Results: Clinicians discussed their expectations for high-quality communication (e.g., discussing disease understanding, assessing goals of care) and better integration of palliative care services. Clinicians expressed barriers to delivering that care, including poor inter-clinician communication. To address barriers, clinicians outlined potential intervention points, such as building collaborative models of care, and structural triggers to identify patients who may be appropriate for palliative care., Conclusion: Interventions to address gaps in palliative care delivery for people living with CKD should incorporate systematic identification of patients with palliative care needs and structural mechanisms to meeting those needs via specialty and primary palliative care., (Copyright © 2022 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.)