Nutrient Flows and Balances in Mixed Farming Systems in Madagascar

Mixed farming systems are still prevalent in sub-Saharan Africa. In these systems, the recycling of nutrients through crop-livestock integration (CLI) practices is crucial for the sustainability of soil fertility and crop production. The objective of this study was to analyze nutrient (N, P, K) flows and balances of mixed farming systems to assess CLI contribution to the performance of those systems. We hypothesized that more intensive farms had a better nutrient balance at the farm level, and that improved biomass management methods improved their nutrient balance. Nine farms in the Madagascar highlands were selected, some corresponding to poor traditional farms with only draft cattle; some small or medium-sized, more intensive farms with a dairy herd; and some of the latter with some improvement to management methods of livestock effluents (manure composting, liquid manure collection). The nutrient balance of the farming systems was determined, and performance indicators were calculated at both farming, livestock, and CLI levels. Results showed that nutrient recycling through CLI is significant in the functioning of the systems studied, contributing primarily to circulating nutrient flows (up to 76%) and leading to greater efficiency and productivity. Nutrient flows resulting from these practices mainly concerned animal feeding (higher than 60% of nutrient flows), even if manure management was central for crop fertilization and that manure remained a desired animal product of these types of farms (up to 100% of animal products). Large negative balances of N and K (up to 80% of inputs) were observed in traditional livestock systems with draft cattle. They were smaller (39–68%) in more intensive dairy farms. Composting of manure did not decrease negative balances, whereas their magnitude was significantly reduced by the collection of liquid manure (19% for N; 42% for K). Better management of biomass at the farm level, in particular the collection of liquid manure, seemed to substantially reduce nutrient losses in MFS.

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.

Integrated Nutrient Management Improves the Growth and Yield of Rice and Greengram in a Rice—Greengram Cropping System under the Coastal Plain Agro-Climatic Condition

Continuous mono-cropping of rice has resulted in decline or stagnation of yield output due to the occurrence of multiple nutrient deficiencies and worsening of soil physicochemical properties accompanying increased pressure of insect pests and diseases. The basic concept of integrated nutrient management (INM) is maintenance or adjustment of soil fertility and supply of plant nutrients to an optimum level for sustaining the desired crop productivity through optimisation of benefits from all possible sources of plant nutrients in an integrated way. Augmenting a rice-based cropping system with pulses is a prevalent and indigenous cropping system under rainfed conditions. Considering the above facts, experiments were conducted to evaluate the impacts of integrated nutrient management on productivity of aromatic rice–greengram cropping system and nutrient balance of the post-harvest soil for agricultural sustainability under rainfed conditions in two consecutive years (2017–2018 and 2018–2019) with six main plots and three subplots. The experimental findings revealed that the treatment comprised of 50% recommended dose of fertiliser (RDF) through chemicals + 50% recommended dose of nitrogen (RDN) through farmyard manure (FYM) increased the plant height, tillers, dry matter accumulation, leaf area and leaf area duration, and yield parameters in short grain aromatic rice. Similarly, preceding application of 50% RDF + 50% RDN through FYM to rice and further application 75% RDF + Rhizobium+ phosphate solubilizing bacteria (PSB) to greengram increased the growth characteristics and yield parameters—such as pods/plant, seeds/pod, grain yield, stover yield, and harvest index—in greengram. It was concluded that the treatment consisting of 50% RDF (chemical fertiliser) + 50% RDN (FYM) to rice and 75% RDF + Rhizobium + PSB to greengram increased the productivity of the rice–greengram cropping system. Furthermore, the adoption of INM has positively impacted post-harvest soil nutrient balance.

Effects of sequential feeding with adjustments to dietary amino acid concentration according to the circadian rhythm on the performance, body composition, and nutrient balance of growing-finishing pigs

This study aimed to evaluate the effects of a sequential feeding program (SEQ) with diets varying in amino acid (AA) concentrations in the first and last 12 h of the day on the performance, body composition, and nutrient balance of growing-finishing pigs. Sixty-eight castrated male pigs were distributed in four treatments: a daily feeding program (DP) and three SEQs. In the DP, dietary requirements of AA were adjusted daily. In the SEQ, dietary daily requirements of AA were adjusted every 12 h, providing a low AA concentration in period 1 (P1; 00:00–11:59 h) and a high AA concentration in period 2 (P2; 12:00–23:59 h). In the SEQ, three different levels of low and high AA concentrations were evaluated: ±20%, ±30%, and ±40%. The experiment lasted 82 days and was divided into phase 1 (25–50 kg body weight; BW), phase 2 (50–70 kg BW), and phase 3 (70–100 kg BW). During phase 1, irrespective of dietary AA concentration, SEQ pigs had higher lysine intake, protein gain, and phosphorus efficiency than DP pigs (P ≤ 0.05). Pigs in the SEQ showed a tendency for greater average daily gain, body protein, and body lipids compared to the DP pigs (P ≤ 0.10). During phase 2, SEQ pigs showed a tendency for higher average feed intake in P2 compared to DP pigs (P = 0.07); consequently, average daily gain, body protein, and phosphorus retention tended to increase (P ≤ 0.10). During phase 3, SEQ pigs had a higher average feed intake in P2 than DP pigs (P = 0.03). However, they had a similar body composition (P > 0.05) and a tendency for higher nitrogen excretion (P = 0.06) than DP pigs. Our results suggest that SEQ is an effective approach for improving the performance and body composition of growing pigs.

Analysis and Solutions to Environmental Problems in Livestock Farming

The intensifi cation of agricultural production has led to the disruption of nutrient cycles in agroecosystems. In livestock farming, one of the key problems is the low degree of using secondary resources (organic fertilizers based on manure and manure). (Research purpose) To substantiate the basic principles of assessing the agroecosystem environmental sustainability and to develop engineering methods for ensuring environmental safety in livestock farming. (Materials and methods) To solve the problems of agroecological assessment, eff ective technology choice and intelligent system creation, the following indicators were used: 1. specifi c density of animals (mainly for macro-assessment); 2. nutrient balance (the diff erence in the amount of nitrogen available in the formed organic fertilizers with environmentally safe consumption); 3. nitrogen losses during the disposal of organic waste from livestock farming; 4.the eff ectiveness of implementing the best available techniques (BAT). (Results and discussion) Using the assessment of indicators 1 and 2 in the case of the Leningrad region, it was revealed that 3 districts are classifi ed as territories with an excessive risk to the environment, 1 district is classifi ed as a territory with a high risk, 5 districts – with an acceptable risk, and 8 districts – with a low risk to the environment. To solve problems in areas with excessive and high load, we conducted an assessment on indicators 3 and 4, which allowed us to explore technical solutions and select the BAT to reduce the environmental burden. The obtained results showed that among the main technical solutions in the fi eld of organic waste management of livestock farming are biofermentation and the introduction of liquid organic fertilizers. Biofermentation in special chambers can reduce emissions of polluting gases by more than 2 times, and speed up the processing process by more than 60 times. To work with liquid organic fertilizers, intelligent machines with low-emission working bodies have been developed to reduce nitrogen losses during application by up to 50 percent. To solve the problems of agricultural monitoring and engineering solution management, a digital system has been developed that allows to model scenarios of technological development and their impact on the agroecosystem environmental sustainability. (Conclusions) The results obtained allow us to systematically analyze the problems of agroecosystem environmental sustainability and propose specifi c technical and optimization solutions for livestock farming.

Efficacy of Cicer arietinum L. & Vigna mungo L. in remediation of Hexavalent Chromium

Hexavalent Chromium is a major soil pollutant; thus, its remediation from soil deserves due attention. Phytoremediation is an area of active current research which is eco-friendly and economic. Use of leguminous plants for phytoremediation will improve soil quality, fertility and nutrient balance and would help in restoration of natural soil ecosystem. The present study focuses on the use of two commonly growing legumes; Cicer arietinum (RP1) and Vigna mungo (RP2) to explore their remediation potential towards Cr(VI) with concentration ranging from 100-900 mg kg−1 with the growth up to three weeks and were assessed for remediation potential and toxicity parameters. Higher percentage of decrease in root and shoot length was observed in RP2 as compared to RP1. Chlorophyll content was also found to be decreasing with increasing Cr stress in both the species. RP2 recorded higher BCF than RP1. Highest bioaccumulation factor 4.32 was observed in RP2 at 400 mg kg−1 concentration. Translocation factor >1 was observed in both the plants with highest as 1.67 at 600 mg kg−1 in RP2 and 1.93 at 400 mg kg−1 in RP1. Remediation percentage of 72.25% in RP2 at 600 mg kg−1 and 73.13% at 400 mg kg−1 in RP1 was observed. Both the plants showed high tolerance and remediation potential towards Cr(VI) therefore has a great phytoremediation prospect, however, RP2 can be preferred over RP1.