Impact Of Changes In Management Research Articles

A 10-year review of presentation, management and outcomes of STEMI in a high-volume regional tertiary Australian centre

ObjectiveTo assess the trends and impact of changes in management of ST Elevation Myocardial Infarction (STEMI) from 2010 to 2019. DesignRetrospective analysis of data from STEMI hospitalisations including demographic, comorbidity, angiographic and outcome data. Setting/participantsHigh-volume non-surgical regional Australian tertiary referral centre. Main outcome measurementsIndex & 12-month mortality (all-cause & cardiovascular), door-to-balloon time, target-vessel failure, target-vessel revascularisation & procedure-related bleeding. ResultsFrom 2010 to 2019, 1299 patients presented with STEMI. The cardiovascular risk factor profile did not significantly change over the 10-year study period, p = 0.23. There was a significant trend toward culprit vessel percutaneous coronary intervention with stenting, rather than balloon angioplasty followed by surgical revascularisation, p = 0.029. The mean door-to-balloon time was 88 +/− 5.7 min and demonstrated a statistically significant improvement across the decade, p = 0.035. Radial access became the preferred angiographic approach (2010 92% femoral, 2019 91% radial). Drug-eluting stents (DES) replaced bare metal stent use. There was a statistically significant reduction in 12-month cardiovascular mortality across the decade (p = 0.042). However index hospitalisation (cardiovascular and all-cause) and 12-month all-cause mortality did not reduce. Young patients and women are important sub-groups of STEMI presentations with different risk factor profile. ConclusionsAdvances in management of STEMI such as radial access, use of DES and a significant reduction in door-to-balloon time across the decade resulted in a reduction of 12-month cardiovascular mortality over the decade however there was no significant reduction in 12-month all-cause mortality, or index hospitalisation cardiovascular or index hospitalisation all-cause mortality. Further research is needed to ensure non-mortality outcomes, such as heart failure hospitalisation and quality of life, also demonstrate temporal improvement with STEMI management advances. Earlier cardiovascular risk assessment should be considered in smokers than is currently recommended in Australian guidelines (≥45yo for most individuals).

Evaluation of the Impact of Management Changes on Midwives' Attitudes: A Questionnaire-Based Comparative Study in a a Women's and Children's Hospital in China: A Questionnaire-Based Study.

BACKGROUND Change management has become an important tool for hospitals to continuously improve themselves in a competitive market. This questionnaire-based study aimed to compare the attitudes of 78 midwives before and after management changes in work schedules and performance-related pay between March and October 2022 at a women's and children's hospital in China. MATERIAL AND METHODS The survey utilizing a job involvement scale and a self-designed questionnaire was distributed through WeChat group chat for all midwives of the hospital. The hospital has 87 midwives. A total of 78 midwives participated in the questionnaire survey. RESULTS The midwives' score ranges of work initiative, work attitude, work value, work recognition, and work enthusiasm and focus before change management were 21-39, 19-37, 23-29, 12-18, and 12-20, respectively, but that after change management they were 22-39, 19-37, 23-30, 13-18, and 14-23, respectively. After change management, both of the P values for work attitude and work enthusiasm and focus were less than 0.05, 80.23% of the midwives were willing to work across the 2 campuses, and all surveyed midwives agreed on unified accounting of performance pay under the condition of working across the 2 campuses. Their views changed from "maintaining the status quo: taking the initiative - passive resistance" to "questioning" to "openness to change: acceptance". CONCLUSIONS The change management implemented within our department is feasible and the clinical risk is controllable. More attention was paid to the midwives' perceptions and humanized management was applied during change management, leading to a success of change.

Management of Student Character Education in the Globalization Era (Case Study in Wali Songo Islamic Boarding School Ngabar Ponorogo)

To make students have noble characters (good behavior), institutions will always look for good ways to instill character values in students, including the institution that the author examines, Wali Songo Ngabar Ponorogo Islamic Boarding School. In Wali Songo Islamic Boarding School, since the boarding school holds activities, then, in these activities there are character values instilled in students, as the main source in the implementation of social life must have a character that can humanize humans so that in social activities there are limits to the existence, administration, and manners that every human being must have. This research uses a qualitative approach, and the type of research is descriptive qualitative with a case study approach, while the problem formulations in this thesis are: (1) How are the planning, implementation, and activation of programs at Wali Songo Ngabar Ponorogo Islamic Boarding School? (2) How does the boarding school support character education at Wali Songo Ngabar Ponorogo Islamic Boarding School? (3) And how is the impact of changes in the management of student character education at Wali Songo Ngabar Ponorogo Islamic Boarding School? This thesis is very helpful for the author in adding insight into mindsets, attitudes, and experiences in character-building efforts. They produce social life, namely making programs that are useful for the development and formation of student character. From the results of this study, the authors concluded that: (1) Planning, implementing, and supervising the programs of the student’s parents of Wali Songo Ngabar Ponorogo Islamic Boarding School in implementing character education through activity programs in the boarding school that have been agreed upon by the leader of the boarding school and other administrators (administrators through discipline and giving rules or giving examples or actual examples from the boarding school environment, (3) The impact of changes in education management on the character of students from students’ parents is the increased trust of parents or students guardians to send their children to boarding schools whose graduates are accepted in quality schools, accepted in the community.

Using intervention analysis to evaluate the trends in release rates of recreational fisheries following extensive management changes

Changes to management of a fisheries resource are often required to ensure ongoing sustainability. However, such changes can sometimes lead to unintended effects such as increased release rates and associated post-release mortality. These effects may be highly variable between species and areas. Recreational fishing management changes were introduced on the west coast of Australia in 2009/10 to recover stocks of demersal scalefish. Key changes included reducing mixed species bag limits across management zones and increasing the minimum size limit for one species in some management zones. The restrictive catch limits resulted in increased release rates of key demersal species. However, whether such increases are significant and sustained over time, and thus of management concern, have not been evaluated. We carried out intervention time series analysis to evaluate the impact of management changes on release rates of four key demersal species for the recreational sector in metropolitan and regional management zones covering ∼8° latitude using an 18-year time series of charter recreational fishery data from July 2002 to January 2020. We observed varying responses in release rates by species and zones, the most common of which were a step increase, a ramp and a temporary increase that decayed. These responses may be related to targeted management changes which influenced fisher behaviour, perceived recreational value of some species and recruitment variation. Our study demonstrates that intervention analysis, which has seen limited use in this context, can assist in evaluating the impact of management changes on different species for recreational fisheries.

Analysis of Factors Affecting Auditor Switching

This research aimed to determine the impact of management changes, company growth, financial distress, and the percentage change in ROA, KAP size, and company size on auditor switching. In this study, the management changes and KAP size employed dummy variables. The company growth is projected by its delta revenue percentage; financial distress is projected by its debt to equity ratio (DER); the percentage change in ROA is projected by its delta return on asset (ROA); and the size of the company is projected with the natural logarithm of total assets. This research was conducted on manufacturing sector companies listed on the Indonesia Stock Exchange (IDX) from 2017–2019. The sampling technique applied in this study was the purposive sampling technique. The sample in the study was 68 companies, and it was conducted over three years, resulting in 204 data. The employed data analysis technique was logistic regression analysis. The results showed that the variable percentage change in ROA and KAP size affected auditor switching. Meanwhile, the variables of management changes, company growth, financial distress, and company size do not affect auditor switching.

Optimal medical management in patients undergoing peripheral vascular interventions for chronic limb-threatening ischemia is associated with improved outcomes

ObjectiveOptimizing medical management and risk factor modification are underused strategies in patients with chronic limb-threatening ischemia (CLTI), despite evidence of improved outcomes. The Vascular Quality Initiative (VQI) registry is a tool to improve quality of vascular care. In this study, we used the VQI to evaluate trends in medical management in patients with CLTI undergoing peripheral vascular interventions (PVI), and the impact of changes in management on overall survival (OS), amputation-free survival (AFS), and limb salvage (LS). MethodsPatients undergoing index PVI for CLTI between 2012 and 2016, with ≥24 months of follow-up were identified from the national VQI registry. Patient details including smoking status and medication use, OS, LS, and AFS were analyzed with linear-by-linear association, t test, and logistic regression. ResultsThere were 12,370 PVI completed in 11,466 patients. There was a significant increase in infrapopliteal interventions (from 29.8% to 39.0%; P < .001) and PVI performed for tissue loss (from 59.1% to 66.5%; P < .001). The percentage of current smokers at time of PVI decreased (from 36.2% to 30.7%; P = .036). At discharge, statins were initiated in 25%, aspirin in 45%, and P2Y12 therapy in 58% of patients not receiving these medications before PVI. Over the course of follow-up, dual antiplatelet therapy (DAPT) (from 41.1% to 48.0%; P < .001), angiotensin-converting enzyme (ACE) inhibitor (from 46.2% to 51.3%; P < .001), and statin (from 70.4% to 77.5%; P < .001) use increased. Combined DAPT, ACE inhibitor and statin use increased from 33.6% to 39.6% (P ≤ .001). Significant improvement in 24-month OS and AFS was noted (OS, from 90.9% to 93.7% [P = .002]: AFS, from 81.2% to 83.1% [P = .046]), but not LS (from 89.6% to 89.0%; P = .83). Combined therapy with P2Y12 inhibitors, statins and ACE inhibitors was an independent predictor of improved OS (hazard ratio, 0.61; 95% confidence interval, 0.39-0.96; P = .034). DAPT was independent predictor of improved LS (hazard ratio, 0.83; 95% confidence interval, 0.79-0.87; P < .007). ConclusionsAntiplatelet, ACE inhibitor, and statin use increased over the study period and was associated with improved OS and AFS. LS trends did not change significantly over time, possibly owing to the inclusion of patients with a greater disease burden or inadequate medical management. Medical management, although improved, remained far from optimal and represents an area for continued development.

Study on WD Petrochemical Company Safety Management Improvement

The study takes the safety management of a domestic petrochemical company as the research object, collects and summarizes relevant information, and analyses the current situation in four aspects, including its organizational structure, safety management system, safety culture construction and behavioral control, so as to identify the problems that exist, such as the adverse impact of management changes, the lack of depth in the construction of safety management system, and the lack of strength in the construction of safety culture. The study also compares and draws on the safety management concepts and systems of well-known domestic and international chemical companies such as DuPont, Toyota and Sinopec, for example, establishing the concept that safety investment is efficiency and extending production safety to the lives of employees, and proposes measures to absorb and apply these achievements in the context of the actual situation of the company. The study proposes a "1-2-4 model" based on the existing "2-4 model" of accident causation: a safety information platform, two levels of organization and individual, the root cause of culture, the fundamental cause of system, the indirect cause of employee awareness and knowledge, and the direct cause of employee behavior. In view of the problems of enterprise safety management, based on the model, this paper proposes measures to improve WD's safety management, including planning, creating a safety information platform, establishing a safety management organization and employing professional staff, introducing solid system construction and benchmarking activities, cultivating a progressive corporate culture, creating a good working atmosphere, truly putting people first, putting strong training and education in place, raising staff safety awareness, teaching employees about safety, adopting effective motivational methods, etc. This will promote the continuous updating and improvement of WD's safety management and ensure a healthy and sustainable development of the company as well as a harmonious community business relationship.

Changes in Cancer Management due to COVID-19 Illness in Patients with Cancer in Northern California.

The response to the COVID-19 pandemic has affected the management of patients with cancer. In this pooled retrospective analysis, we describe changes in management patterns for patients with cancer diagnosed with COVID-19 in two academic institutions in the San Francisco Bay Area. Adult and pediatric patients diagnosed with COVID-19 with a current or historical diagnosis of malignancy were identified from the electronic medical record at the University of California, San Francisco, and Stanford University. The proportion of patients undergoing active cancer management whose care was affected was quantified and analyzed for significant differences with regard to management type, treatment intent, and the time of COVID-19 diagnosis. The duration and characteristics of such changes were compared across subgroups. A total of 131 patients were included, of whom 55 were undergoing active cancer management. Of these, 35 of 55 (64%) had significant changes in management that consisted primarily of delays. An additional three patients not undergoing active cancer management experienced a delay in management after being diagnosed with COVID-19. The decision to change management was correlated with the time of COVID-19 diagnosis, with more delays identified in patients treated with palliative intent earlier in the course of the pandemic (March/April 2020) compared with later (May/June 2020) (OR, 4.2; 95% CI, 1.03 to 17.3; P = .0497). This difference was not seen among patients treated with curative intent during the same timeframe. We found significant changes in the management of cancer patients with COVID-19 treated with curative and palliative intent that evolved over time. Future studies are needed to determine the impact of changes in management and treatment on cancer outcomes for patients with cancer and COVID-19.

Spatio-temporal variations in mortality during the seawater production phase of Atlantic salmon (Salmo salar) in Norway.

In a sustainable production of animals, monitoring and minimizing mortality must be a top priority. Systematic measuring of mortality over time can be used to evaluate the impact of changes in management and production strategies in Norway. To aid understanding of the potential for reducing mortality, we have used data from 2014 to 2018 to investigate the spatio-temporal patterns of mortality, by descriptive analyses and statistical modelling of possible determinants of mortality. The results show large differences in mortality across different production zones and between years. The areas with the highest density of farmed salmon are also the ones with highest mortality. The total cumulated mortality of farmed salmon increased from 32.3 million in 2014 to 35.2 million in 2018, corresponding to 14.3% and 15.8% of the standing stock. An initial higher mortality was observed during the first 3months after stocking (mean: 1.5% [0.9%-8.6%] mortality/month). This was followed by a period of stability and lower mortality (mean: 0.8% [0.9%-3.1%] mortality/month), until month 10, when mortality started to increase again. The month of first stocking, the year of slaughter, production zone and number of months at sea were all found to be statistically significant determinants for mortality, with p-values<1e-15.

The relationship between management changes and corporate debt costs based on engineering management

This paper takes the companies with management changes in the construction industry of Shanghai and Shenzhen in 2013-2017 as a sample, and uses the PSM-DID method to explore the impact of management changes on debt costs. The results show that the corporates’ debt costs for management changes are significantly higher than companies that have not experienced management changes. Further research found that when management change types are abnormal changes and management successors are external successors, management changes result in higher debt costs. This research provides a basis for the management decision-making of engineering management and gives useful suggestions for its engineering management.

203. A national surveillance approach to monitor incidence of eclampsia in the Netherlands: The Netherlands obstetric surveillance system (NethOSS)

Introduction In 2004–2006, the incidence of eclampsia was more than twice as high in the Netherlands as compared to the United Kingdom. Since this comparison of these nationwide collected data, many efforts have been made to decrease the incidence of eclampsia and its related complications. Objective To determine the current incidence of eclampsia in the Netherlands and the impact of management changes ten years after the previous nationwide assessment. Methods Cases of eclampsia were prospectively collected using the newly established Netherlands Obstetric Surveillance System (NethOSS) in all hospitals with a maternity unit in the Netherlands. Complete casefile copies for 2013–2016 were used for comparative analysis of individual level data with the previous cohort (2004–2006). Results The monthly card return rate was 97%; 88 women with eclampsia were identified. Incidence decreased from 6.2/ 10 000 in 2004–2006 to 1.8/ 10 000 deliveries (RR 0.28, 95% CI 0.22–0.36). We observed an increase in the use of antihypertensive medication (61/82 versus 35/216; RR 18.4, 95% CI 9.74–34.70) and magnesium sulfate (82/82 versus 201/216; RR 1.08, 95% CI 1.04–1.12). In the current registration, target blood pressure was achieved after a median of 145 min (IQR 74–322) in case of severe hypertension. There was a decrease in perinatal mortality from 3.0/ 100 000 in 2004–2006 to 0.2 per 100 000 deliveries (RR 0.08, 95% CI 0.01–0.60). Maternal death occurred in one woman compared to three in the previous registration. Discussion This study demonstrates a considerable reduction in the incidence of eclampsia and illustrates the potential success of management strategies suggested by emerging evidence in recent years. At the same time, there is a possibility for further reduction in incidence by introducing specific algorithms for a goal-directed management approach and stricter adherence to guidelines.

Simulated Soil Organic Carbon Responses to Crop Rotation, Tillage, and Climate Change in North Dakota.

Understanding how agricultural management and climate change affect soil organic carbon (SOC) stocks is particularly important for dryland agriculture regions that have been losing SOC over time due to fallow and tillage practices, and it can lead to development of agricultural practice(s) that reduce the impact of climate change on crop production. The objectives of this study were: (i) to simulate SOC dynamics in the top 30 cm of soil during a 20-yr (1993-2012) field study using CQESTR, a process-based C model; (ii) to predict the impact of changes in management, crop production, and climate change from 2013 to 2032; and (iii) to identify the best dryland cropping systems to maintain or increase SOC stocks under projected climate change in central North Dakota. Intensifying crop rotations was predicted to have a greater impact on SOC stocks than tillage (minimum tillage [MT], no-till [NT]) during 2013 to 2032, as SOC was highly correlated to biomass input ( = 0.91, = 0.00053). Converting from a MT spring wheat (SW, L.)-fallow rotation to a NT continuous SW rotation increased annualized biomass additions by 2.77 Mg ha (82%) and SOC by 0.22 Mg C ha yr. Under the assumption that crop production will stay at the 1993 to 2012 average, climate change is predicted to have a minor impact on SOC (approximately -6.5%) relative to crop rotation management. The CQESTR model predicted that the addition of another SW or rye ( L.) crop would have a greater effect on SOC stocks (0- to 30-cm depth) than conversion from MT to NT or climate change from 2013 to 2032.

Erratum: Regression‐Kriged Soil Organic Carbon Stock Changes in Manured Corn Silage–Alfalfa Production Systems

Soil Sci. Soc. Am. J. 81:1013–1013 doi:10.2136/sssaj2017.04.0138 In the paper “Regression-Kriged Soil Organic Carbon Stock Changes in Manured Corn Silage–Alfalfa Production Systems”, it came to our attention that there was a change in the CN analyzer used for soil C analysis during our study. Our 2006 soil samples were analyzed with a LECO CN-2000, while our 2015 samples with a LECO TRU-SPEC CN. It was discovered that these instruments differed in the amount of OM that was combusted from the samples, with estimates for 2006 SOC being 3 to 8% low because of partial combustion by the LECO CN-2000. A re-analysis was made of the 2006 SOC data, and also a recalculation was made of the changes in SOC from 2006 to 2015 for our two study fields. Previously, we showed significant gains in the West field from 0 to 15 cm; now the gains are not significant. Likewise, we previously showed non-significant losses in the East field from 0 to15 cm, now the losses are significant at P < 0.05. Gains in the lower depths (30–60 and 60–90 cm) also reduced to non-significant changes. The conclusions for the 15- to 30-cm layer didn't change for either field. Therefore our conclusion about the impact of management changes. The previous conclusion: “After 10 years of monitoring, SOC stocks to the 90-cm depth have been maintained or increased at this farm, suggesting that typical field management practices associated with large, modern dairies can sequester SOC”. The new conclusion: “After 10 years of monitoring, SOC stocks to the 90-cm depth have been maintained where manure was injected and alfalfa included in rotation with silage corn, but declined in another field where manure was fertigated and only silage corn was grown”. This does not impact our conclusion about the appropriateness of regression kriging for assessing changes in SOC. Shown below is the reanalyzed and recalculated data for the affected samples.

Case report

150-cow Holstein dairy herd was experiencing a higher than desirable incidence of displaced abomasum (8% all lactations), ketosis (60% lactation 1, 75% lactation 2 and greater), and metritis (70% lactation 1, 30% lactation 2 and greater) in transition cows. The producer initially refused to implement recommended management changes that would have potentially improved transition cow health of the herd. The increased incidence of transition cow disease, along with the producer’s reluctance to make management changes, led the nutritionist and the veterinarian to partner to utilize The Vital 90™ Days risk assessment tool (dRisk) and economic assessment tool (dEconPro) as a way of identifying and motivating management changes. The results from the dEconPro showed a pre-management (1 year prior = group PRE) to post-management (1 year after = group POST) reduction in total cost per calving of $269 due to decreased incidence of ketosis, metritis, and displaced abomasum. There was significant parity-by-group interaction for milk production, with first-lactation POST cows producing more first-test milk than PRE (68.1 vs 63.5 lb [30.9 vs 28.8 kg], P=0.05). There was a tendency for more peak milk and more total 305ME milk for POST vs PRE (84.6 vs 81.0 lb [38.4 vs 36.7 kg], P=0.13 and 25,995 vs 24,953 lb [11,791 vs 11,319 kg], P=0.10 respectively). There was no difference in multiparous cows, and no difference in removals by 60 or 400 DIM for all cows. For reproductive performance, there was a tendency for higher odds of successful first service for POST vs PRE (1.83, P=0.14), but no difference in time to pregnancy through 200 DIM. The results show that The Vital 90 Days dEconPro and dRisk proved to be extremely valuable tools to help motivate positive change on this dairy. The main objective of this case study was to demonstrate how the team approach on a dairy farm could combine with the use of transition cow risk- assessment tools to validate management recommendations and quantify the impact of management changes.

Impact of Management Changes on Loco-Regional Control of Breast Carcinoma: A 30-year Single Institution Experience Breast Cancer: Basic and Clinical Research

Purpose: This institutional-based study aims to reflect changes in diagnosis, surgery, radiotherapy, systemic therapy by retrospectively analysing treatment modalities and outcome during the past 30 years of breast cancer. We hypothesized these changes result in better outcome.Material and methods: 2990 women are included, aged 18–95, no previous cancer, unilateral stage I-III primary breast tumors, breast-conserving surgery (BCS) or mastectomy (ME), postoperative radiotherapy (RT) and where indicated systemic treatment. Patients were divided in 3 cohorts stratified by year of diagnosis: 1984-1991, 1992- 1999 and 2000-2008. The interval of cohorts was based on institutional changes in systemic regimens.Results: Over time, median age at diagnosis was similar, patients >70 year increased (19.5 to 25.7%). Over the 3 cohorts: stage migration is observed, determination of tumor grading became routine, proportions of known ER/PR status increased. Over time an obvious shift to less mutilating surgery is observed. Systemic treatment increased significantly during the observed period.In stage I disease, overall (OS), local control (LC) and disease free survival (DFS) didn’t change. In stage II, a significant increase in 10 years OS and DFS (p= 0.02 and 0.001) is observed. In stage III we noticed a significant increase in 10 years DFS (p=0.04) and trend in increase of 10 years OS (p= 0.06). Local Recurrence free survival (RFS) didn’t change significantly for all stages.Conclusion: This study demonstrated an improved outcome for stage II and III over time in our population with the same local control. This is multifactorial, reflecting changes in diagnostic imaging, surgery and increased use of systemic therapy.

P08.21 The impact of changes in management of glioblastoma (GBM) since the introduction of chemo-radiation (chemoRT)

P08.21 The impact of changes in management of glioblastoma (GBM) since the introduction of chemo-radiation (chemoRT)

Stan wdrożenia zmian w zarządzaniu organizacjami z sektora kultury i sektorów kreatywnych wynikających ze zmian w otoczeniu

The aim of the study is to identify the state of implementation of changes in management in organizations in the cultural and creative sectors resulting from changes in the environment. This was done by reviewing the ideas presented in the literature and conducting own empirical research. The research was both quantitative and qualitative, based on a questionnaire. It was carried out in 2015, on a group of 101 representatives of organizations from the cultural and creative sectors. Respondents were interviewed about the necessary changes in management resulting from changes in the environment and the state of implementation of these changes in the organizations in which they work. The results were statistically analyzed. Differences in the responses from the point of view of the gender of the respondents have been identified. The difference between the granted significance of the change and the degree of its implementation was also determined. Comparisons were done for independent samples, using the Kolmogotow-Smirnov test and non-parametric statistics, using the statistical package IBM SPSS version 21.0. It turned out that only part of the respondents have a full awareness of the scope and the impact of changes in management on functioning of organizations in the sector. The state of implementation of these changes in the organizations of the cultural and creative sectors is still low.

Cell wall compositional changes during incubation of plant roots measured by mid-infrared diffuse reflectance spectroscopy and fiber analysis

Plant roots, particularly the constituents of root cell walls (hemicellulose, cellulose and lignin) are important contributors to soil organic matter. Little is known about the cell wall composition of many important crop species or compositional changes as roots decay. The objectives of this study were to quantify changes in root cell wall composition during a four week laboratory incubation by forage fiber analysis and characterize those changes using diffuse reflectance infrared fourier transform spectroscopy (DRIFTS). The roots of six important crop, forage and native grass species were incubated at 25°C and sampled weekly. Alfalfa lost 78% of initial mass over four weeks, while the remaining species lost between 19% and 38%. For all species the majority of this loss occurred during Week 1, and only alfalfa mass loss was significant (P<0.05) each week. The trends observed for whole root decomposition were paralleled by the decomposability of root cell walls. Significant changes in hemicellulose, cellulose and lignin concentrations over time were only observed in alfalfa roots. Significant changes in decomposability of these constituents was likewise only observed in alfalfa, with cellulose the most decomposable fraction, followed by hemicellulose and lignin. Analysis by DRIFTS supported the fiber analysis results and revealed important changes in root cell wall composition. The disappearance of peaks due to starch in the perennial alfalfa and switchgrass roots following Week 1 helped to explain the greater initial mass loss in both of these species relative to the roots of the annuals. The spectral data also illustrated the resistance of alfalfa lignin to decomposition, the preservation of carbonyl compounds and the degradation of readily decomposed proteins. Finally, changes potentially indicative of wax compound preservation were found in the DRIFTS spectra of alfalfa even though the amount of wax was too small to quantify by fiber analysis. This research study reveals differences in the rate at which crop roots decompose and important changes that can occur in readily decomposable roots over relatively short time scales. These results provide valuable information contributing to the understanding and prediction of short term soil organic matter dynamics which will help to predict possible impact of management changes or soil disturbance on soil health and productivity as well as long term organic C stabilization and the potential for C sequestration.

Managing the herbage utilisation and intake by cattle grazing rangelands

Rangelands throughout the world provide clean water, fix solar energy in plants, sequester carbon, and offer recreational opportunities, with other ecosystem goods and services, including food from wild and domestic herbivores. Grazing rangelands with cattle requires constant management to balance the economic sustainability of the farm with other ecological services that rangelands provide. The challenges in management arise from the diversity of the rangeland forage resources at extremely large spatial and temporal scales. To be able to predict the performance of cattle grazing in extensive rangeland environments, estimating herbage intake is paramount because it quantifies energy intake and performance. Nutrient demand is the major driver of herbage intake, and characteristics of the sward and terrain of the landscape dictate how this demand is met. System models that integrate changes in weather patterns and herbage over long periods of time will allow farmers and scientist to monitor changes in herbage mass and utilisation. Dynamic models that include herbage growth components sensitive to weather patterns and animal demands are needed to predict how long-term changes in beef herd management will affect performance and range condition. Vegetation indexes captured across biomes with satellites can accurately quantify the dynamics of aboveground net primary production and changes in nutritional value with confidence. The computer software, PCRANCH, is a program for simulating cow–calf herd dynamics over long periods of time. The models within the PCRANCH software can simulate herbage growth and animal utilisation at large spatial and temporal scales needed for rangeland management and allow ranchers to evaluate the impacts of management on other ecological services. Knowing the long-term impact of management changes on swards enable ranchers to anticipate the ecological and economic benefits of improvements or demonstrate a protection of current ecological services.

A regional audit of nitrogen fluxes in pampean agroecosystems

Calculations of nitrogen (N) budgets can help in the understanding of agroecosystem functioning and in proposing more sustainable management strategies. Changes in the main N fluxes of the pampean agroecosystems of Argentina were calculated over time. The impact of management changes on regional N budget and possible future trends were estimated. Changes in land use were quantified using national censuses data. Biological N fixation of leguminous forages was assessed using a regression model and local field experimental data. Nitrogen fixation by soybean, the most extensive grain crop, was calculated using an existing model. Fertilizer input was based upon farmer surveys, and atmospheric N input estimated using local data. Nitrogen output by grain harvest was estimated using national yield statistics and averaged grain N concentration derived from many field experiments widespread over the region. During the last 50 years cropped area has doubled as a result of the widespread adoption of soybean as the main component of rotations. The agricultural expansion included areas previously used for grazing on seeded pastures and seasonal graminaceus forages. The historical N budget of the entire region was positive but has dropped from 2.0Mty−1 in 1960 to 1.3Mty−1 at present. This reduction implies that N fixation by soybean and fertilizer application were lower than the previous livestock/pasture systems N input. During the cropping phase of rotations the N budget was usually negative in the past. Currently, in low yielding areas of semiarid environments, the N budget turned positive; meanwhile in humid climates with high productivity scenarios it remained negative. Fertilizer rates applied balanced N output in the former case but not in the latter. Partial factor productivity of N inputs increased from 3- to 6-fold during the last 50 years in the Pampas. Uncertainties related to the estimations performed are discussed.