Soil Nutrient Balance and Stock on Smallholder Farms at Agew Mariam Watershed in Northern Ethiopia

IntroductionSoil nutrient balance is used to evaluate the state of soil fertility, rate of nutrient depletion, sustainability of land productivity, the environmental wellbeing of an area, and to take appropriate management decisions. This study was conducted to quantify soil nutrient balance and stocks on smallholder farms at the Agew Mariam watershed in northern Ethiopia in the 2020/21 main season.MethodsInflows and outflows of nitrogen (N), phosphorus (P), and potassium (K) into, and out of barley, tef, and wheat farms were determined through, field measurement, laboratory analysis, and interviews. The balance quantification was done by subtracting nutrient outputs from the inputs. ResultsThe N partial balance of barley, tef and wheat was -66, -9.8, and -50.7 kg ha-1 yr-1 respectively. The P balance was also -5.9, 0.9, and -2.6 kg ha-1 yr-1 for barley, tef, and wheat respectively. Whereas, K balance was -12.3, -3.2, and -5.4 kg ha-1 yr-1 from barley, tef, and wheat respectively. The balance results revealed that N, P, and K had negative values except for P in tef. Grain yield and crop residue removal were the major paths of nutrient loss. The stock of N was 1295, 1510, and 1240 from barley, tef, and wheat kg ha-1respectively. While, the P stock was 63, 18.7, and 27.5, kg ha-1 from barley, tef, and wheat farms respectively. Similarly, K stock was 1092.7, 1059.4, and 1090.6 kg ha-1 from barley, tef, and wheat cropping systems respectively. ConclusionsReversing the imbalance between inflows and outflows via adding organic and inorganic fertilizers is critically essential for the study area.

Cow Manure Application Cuts Chemical Phosphorus Fertilizer Need in Silage Rice in Japan

Cow manure is a good source of phosphorus (P). Here, we investigated whether the amount of P fertilizer can be reduced when cow manure is applied to paddy soil based on growth, P uptake, yield, and soil P status evaluation. Treatments included unfertilized control (CK); manure plus chemical nitrogen (N), potassium (K), and P fertilizer (MNK P); MNK and 75% P (MNK ¾ P); MNK and 50% P (MNK ½ P); MNK and 25% P (MNK ¼ P); and MNK. Manure was applied at the rate of 10 t ha−1 in fresh weight base. The P fertilizer was applied at 34.9 kg P ha−1 as full dose. Treatment with MNK resulted in the same growth, P uptake, and yield as that with the P fertilizer. P uptake and yield did not respond to P input from chemical fertilizer owing to high soil Olsen P levels. Moreover, MNK could maintain soil Olsen P and total P. Manure application resulted in a positive partial P balance. These results suggest that manure application can cut P fertilizer requirements in P-rich soils, while maintaining soil P for optimal rice growth and yield. By using cow manure in rice production, farmers can conserve finite P resources.

Can Long-Term Experiments Predict Real Field N and P Balance and System Sustainability? Results from Maize, Winter Wheat, and Soybean Trials Using Mineral and Organic Fertilisers

Agri-environmental indicators such as nutrient balance may play a key role in soil and water quality monitoring, although short-term experiments might be unable to capture the sustainability of cropping systems. Therefore, the objectives of this study are: (i) to evaluate the reliability of long-term experimental N and P balance estimates to predict real field (RF) (i.e., short-term transitory) conditions; and (ii) to compare the sustainability of short- and long-term experiments. The LTE-based predictions showed that crops are generally over-fertilised in RF conditions, particularly maize. Nutrient balance predictions based on the LTE data tended to be more optimistic than those observed under RF conditions, which are often characterised by lower outputs; in particular, 13, 44, and 47% lower yields were observed for winter wheat, maize, and soybean, respectively, under organic management. The graphical evaluation of N and P use efficiency demonstrated the benefit of adopting crop rotation practices and the risk of nutrient loss when liquid organic fertiliser was applied on a long-term basis. In conclusion, LTE predictions may depend upon specific RF conditions, representing potential N and P use efficiencies that, in RF, may be reduced by crop yield-limiting factors and the specific implemented crop sequence.

Evaluating the Impact of Crop Layout Changes on N and P Nutrient Balance: A Case Study in the West Liaohe River Basin, China

Regional crop layout has changed significantly due to climate, policy, and other factors, which has impacted farmland nutrient balance. Here, we evaluated the impact of crop layout changes on N and P nutrient balance in the West Liaohe River Basin from 2000–2015. The study area has long been in a N and P surplus state. The unit N surplus exhibited a downward trend and the unit P surplus showed an increasing trend. Significant correlations existed between planting areas and nutrient surplus. The N and P surplus layout was mainly concentrated in the West Liaohe River lower reaches basin. The planting area of wheat must be reduced and the areas of maize and soybean must be controlled to adjust the N and P balance and reduce the environmental pollution risk. Chemical fertilizer and seed inputs are the main sources of N input. Furthermore, combining farming and pastoral farming is conducive to improving N and P use efficiency. Manure can be absorbed by farmland, the ratio of organic and chemical fertilizers can be reasonably set, and chemical fertilizer application can be reduced.

Does Xbox 360 Kinect training improve postural balance in young healthy adults? A preliminary study. (Preprint)

BACKGROUND Balance training in young adults may increase coordination, cognitive function or the symmetry of strength on both sides of the body. It is an essential tool for injury or fall prevention and a precondition for becoming a professional athlete. OBJECTIVE The aim of this study was to assess the effect of Xbox 360 Kinect training on postural balance in young, healthy individuals. METHODS The study enrolled 75 individuals who were randomly assigned to three equal groups. The first group (Group VR) performed exercises on an Xbox 360 Kinect console, and the second group (Group T) performed conventional all-round exercises. The third group was a control group (Group C). Each group underwent balance assessments on the Biodex Balance posturographic platform, including the Balance Error Scoring System test, before and after the training cycle. The level of statistical significance was set at P<.05. RESULTS Group VR and Group T achieved statistically significant improvements in the sway index compared with baseline. Group T gained significant decrease in the sway index on the unstable surface (P=.002). Group VR and group T demonstrated significant decreases in the mean sway index on stable and unstable surfaces (group VR — P=.035; group T — P=.001) Group C did not achieve a statistically significant improvement in the sway index. None of the groups demonstrated a statistically significant decrease in the test error count. CONCLUSIONS Virtual reality in the form of video games played on an Xbox 360 Kinect console may be an effective method of balance training in healthy individuals.

Nutrient Balance as a Tool for Maintaining Yield and Mitigating Environmental Impacts of Acacia Plantation in Drained Tropical Peatland—Description of Plantation Simulator

Responsible management of Acacia plantations requires an improved understanding of trade-offs between maintaining stand production whilst reducing environmental impacts. Intensive drainage and the resulting low water tables (WT) increase carbon emissions, peat subsidence, fire risk and nutrient export to water courses, whilst increasing nutrient availability for plant uptake from peat mineralization. In the plantations, hydrology, stand growth, carbon and nutrient balance, and peat subsidence are connected forming a complex dynamic system, which can be thoroughly understood by dynamic process models. We developed the Plantation Simulator to describe the effect of drainage, silviculture, fertilization, and weed control on the above-mentioned processes and to find production schemes that are environmentally and economically viable. The model successfully predicted measured peat subsidence, which was used as a proxy for stand total mass balance. Computed nutrient balances indicated that the main growth-limiting factor was phosphorus (P) supply, and the P balance was affected by site index, mortality rate and WT. In a scenario assessment, where WT was raised from −0.80 m to −0.40 m the subsidence rate decreased from 4.4 to 3.3 cm yr−1, and carbon loss from 17 to 9 Mg ha−1 yr−1. P balance shifted from marginally positive to negative suggesting that additional P fertilization is needed to maintain stand productivity as a trade-off for reducing C emissions.

Delivering improved phosphorus acquisition by root systems in pasture and arable crops

Improving low efficiency of phosphorus (P) use in agriculture is an imperative because P is one of the key nutrients underpinning sustainable intensification of food production and the rock-phosphate reserves, from which P fertilisers are made, are finite. This paper describes key soil, root and microbial processes that influence P acquisition with a focus on factors that can be managed to ensure optimal use of fertiliser, and development of root systems for improved P acquisition. A case study describes grasslands in southern Australia where the P-balance efficiency of production is very low, mainly because soils are P deficient and moderately to highly P-sorbing. Use of soluble P fertiliser, P-banding and soil testing to guide soil P management ensures effective use of P fertiliser. Progress towards improved P efficiency using pasture legumes with high P-acquisition efficiency is outlined. Development of a ‘whole-of-system’ understanding for effective P acquisition by roots is highlighted.

282 Effect of formulating diets based on a ratio between STTD Ca and STTD P and the inclusion of phytase on the calcium and phosphorus balance of growing pigs

An experiment was conducted to test the hypothesis that formulating diets for pigs based on a ratio between standardized total tract digestible (STTD) Ca and STTD P instead of total Ca and STTD P increases the efficiency of Ca and P utilization. Forty barrows (59.4 ± 3.8 kg) were individually housed in metabolism crates and allotted to 4 corn-soybean meal diets and 2 periods of 11 d in a randomized complete block design. Diets were formulated using a 2 × 2 factorial design with 2 Ca requirement estimates (total Ca or STTD Ca) and 2 inclusion levels of microbial phytase (0 or 500 units/kg). Phytase was assumed to release 0.11% STTD P and 0.16% total Ca. Diets were formulated based on requirements for total Ca and STTD P and the ratio between STTD Ca and STTD P was 1.25:1 in diets formulated based on STTD Ca. Fecal and urine samples were collected from feed provided from d 6 to 9. Data for Ca and P balance were analyzed using a model that included the main effects of diet formulation and phytase level, the interaction between main effects, and the random effect of period. Interactions (P &lt; 0.05) between diet formulation and phytase level were observed for Ca intake, Ca in feces, Ca digestibility, Ca retained as a percentage of intake, P digestibility, P absorbed, and P in urine (Table 1). Despite being provided less (P &lt; 0.05) Ca, pigs fed diets formulated based on STTD Ca did not absorb or retain less Ca than pigs fed total Ca diets, but they absorbed more (P &lt; 0.05) P than pigs fed diets formulated based on total Ca. In conclusion, by formulating diets based on values for STTD Ca, P absorption was increased confirming detrimental effects of oversupplying Ca.

Unbalanced Development

Balance is a powerful idea in economics—in equilibrium economics, in strategies of balanced growth, and many other strategies. This chapter argues for a different understanding of the history of capitalism and, therefore, of policy and strategy. The idea of imbalance is a springboard to explore the ideas of Albert Hirschman. These include the concept of linkages and the dynamics of unbalanced growth (pressures, tensions, and disequilibrium as the motor of change), the principle of the hiding hand, and a focus on unintended consequences and poorly measured side effects of development projects and policies. In line with Hirschman’s ‘possibilism’, we argue that the critiques of large ‘mega-projects’ are misleading. Hirschman also highlighted the difference between economists who think a country’s prospects are determined by its ‘endowments’ (what it is and has) and those more interested in what a country does and becomes through what it does.