Nutrient Management

Table of Contents: •Overview by Gerald C. Nelson •Agricultural Science and Technology Needs for Climate Change Adaptation and Mitigation by Rudy Rabbinge •Reducing Methane Emissions from Irrigated Rice by Reiner Wassmann, Yasukazu Hosen, and Kay Sumfleth •Direct and Indirect Mitigation Through Tree and Soil Management by Brent M. Swallow and Meine van Noordwijk •The Potential for Soil Carbon Sequestration by

En años recientes se ha incrementado el interes y la producción ecológica de cerdos en sistemas al aire libre, considerados por varios autores como una alternativa a los grandes sistemas confinados, por ser respetuosos del comportamiento animal y ambientalmente amigables.  Con el objetivo de estudiar impactos sobre el suelo de un sistema de cerdos en pastoreo luego de 12 años, se muestreó 6 parcelas de 1500 m2 y un área testigo (sin cerdos). El suelo es un Brunosol y las cerdas se manejan en con cargas promedio de 6 cerdas ha-1 año-1, con dieta a base de ración y acceso permanente a pasturas. El sistema produjo modificaciones en propiedades físicas, químicas y biológicas del suelo, generando heterogeneidad espacial en zonas diferenciadas de manejo. La zona de servicio concentró los mayores impactos y la de pastoreo (75% del área) los menores. El sistema ocasionó compactación del suelo, superando los 2 MPa de RP solo en áreas reducidas de la zona de servicio, que fue la más compactada. La MO se redujo de 4,7% en el suelo testigo a 3,9% en el suelo con cerdos en la capa superficial, disminuyendo también 17% en profundidad, explicado fundamentalmente por la disminución de la MONP y sin diferencias significativas entre las zonas de las parcelas. Se incrementó el contenido de P, NO3 y K fundamentalmente en el área de servicio, correlacionados con la conductividad eléctrica del suelo, la cual no llegó a valores problemáticos. El exceso de N fue escasamente acumulado en el suelo, incrementando el riesgo de contaminación de aguas. En la zona de pastoreo el pH disminuyó 0,4 unidades en relación al testigo (p<0,05), la cual no se diferenció significativamente con el área de servicio. Algunos impactos se extendieron en forma significativa (p<0,05) a la capa de 15-30 cm (RP, COS, P, NH4 y CE). No se observó problemas de acumulación de metales pesados (Zn y Cu). Producir cerdos a campo puede ser una alternativa de monores costos de producción a sistemas confinados, pero los resultados sugieren que es una actividad con potencial de generar problemas ambientales por inadecuadas prácticas de manejo.

The requirement under tropical and temperate conditions for water, protein, essential and non-essential amino acids were reviewed. Other basic requirements that comprise energy, micro, and macro minerals and vitamins. Due to multiple benefits and prolificacy of the quails been domesticated, this review on its nutrient requirements is of great essential.

Rice (Oryza sativa L.) and wheat (Triticum aestivum L.) are now grown in sequence on the same land in the same year over 26 Mha of South and East Asia to meet the food demand of a rapidly expanding human population. This rice±wheat (R±W) system brings together con¯icting and complementary practices. Much of the system operates at low yield because of inadequate nutrients and inappropriate water management. The challenge to research is to understand crop responses to the required combination of practices so that management systems can be devised for high and sustainable combined yield. The repeated transitions from anaerobic to aerobic to anaerobic growing conditions affect soil structure, nutrient relations, the growth of the component crops, and their associated pests and diseases. This review establishes realistic yield targets and discusses strategies and tactics to improve complementarity of the two crops by choice of cultivar, sowing time, mechanization, soil and water management, choice and combination of organic and inorganic fertilizers, management of weeds, pests and diseases, and the inclusion of other crops into the system, especially legumes. While research must attend to existing problems and improve resource-use ef®ciency of existing practices, the review suggests the need to look for new production strategies that might avoid existing constraints in some areas of the R±W region. In particular, soil, water and nutrient management strategies, such as reduced tillage and use of raised beds, that avoid the deleterious effects of puddling on soil structure and fertility, improve water-and nutrient-use ef®ciencies, and increase crop productivity, may be appropriate. #

Background Phosphorus (P) is a limiting nutrient in many agroecosystems and costly fertilizer inputs can cause negative environmental impacts. Cover crops constitute a promising management option for sustainable intensification of agriculture. However, their interactions with the soil microbial community, which is a key driver of P cycling, and their effects on the following crop, have not yet been systematically assessed. Scope We conducted a meta-analysis of published field studies on cover crops and P cycling, focusing on plant-microbe interactions. Conclusions We describe several distinct, simultaneous mechanisms of P benefits for the main crop. Decomposition dynamics, governed by P concentration, are critical for the transfer of P from cover crop residues to the main crop. Cover crops may enhance the soil microbial community by providing a legacy of increased mycorrhizal abundance, microbial biomass P, and phosphatase activity. Cover crops are generally most effective in systems low in available P, and may access 'unavailable' P pools. However, their effects on P availability are difficult to detect by standard soil P tests, except for increases after the use of Lupinus sp. Agricultural management (i.e. cover crop species selection, tillage, fertilization) can improve cover crop effects. In summary, cover cropping has the potential to tighten nutrient cycling in agricultural systems under different conditions, increasing crop P nutrition and yield.

... Cradle-to-cradle design: creating healthy emissions – a strategy for eco-effective product and system design. ... Abstract. Eco-effectiveness and cradle-to-cradle design present an alternative design and production concept to the strategies of zero emission and eco-efficiency. ...

Nutrient budgets of agroecosystems are constructed either (i) to increase the understanding of nutrient cycling, (ii) as performance indicator and awareness raiser in nutrient management and environmental policy, or (iii) as regulating policy instrument to enforce a certain nutrient management policy in practice. This paper explores nutrient budgeting approaches and summarizes sources of uncertainty associated with these approaches. Possible implications of uncertainties associated with the different methodologies and approaches for nutrient management and environmental policy are discussed. Three types of nutrient budgets have been distinguished, i.e. farm-gate, soil surface and soil systems budgets. A farm-gate budget is the most integrative measure of environmental pressure, and seems most suitable as environmental performance indicator. A soil surface budget is appropriate for estimating the net loading of the soil with nutrients. Soil system budgets account for nutrient inputs and outputs, recycling of nutrients within the system, nutrient loss pathways and changes in soil nutrient pools; it is the most detailed budget and provides detailed information for nutrient management. Case studies for the dairy farm De Marke indicate that the three budgeting approaches supplement each other. The accuracy and precision of the nutrient budget depend on budgeting approach, data acquisition strategy and type of agroecosystem. There is often a considerable amount of uncertainty in the nutrient budget, due to various possible biases and errors, notably in the partitioning of nutrient losses. Possible sources of biases are personal bias, sampling bias, measurement bias, data manipulation bias and fraud. Sources of errors are sampling and measurement errors. Both biases and errors in nutrient budget estimates may lead to confusion and wrong conclusions. Yet, there is little published evidence that uncertainties are taken into account in decision making. Uncertainties are usually smaller for a farm-gate budget than for a soil surface budget. Therefore, farm-gate budgets are preferred over soil surface budgets as policy instrument. Quantifying uncertainties requires: (a) system identification and analysis, (b) classification of uncertainties, (c) specification of distributions of probabilities of the various sources using Monte Carlo simulation, and (d) monitoring of the nutrient pools, inputs and outputs over time. Analyses of uncertainties in nutrient budgets may provide information about the weakest chain in establishing agri-environmental cause Á/effect relationships and, therefore, may assist to better focus research efforts. Data for the nitrogen budget of The Netherlands indicate relatively large uncertainties for the items denitrification and leaching, with coefficients of variation /30%. In conclusion, there is a need for standard procedures and guidelines in nutrient budgeting and uncertainty analyses, to improve the confidence in and applicability of nutrient budgets. #

Integrated natural resource management (INRM) is considered in the context of evolving crop-livestock systems in West Africa and recent developments in approaches for INRM research. The major crop-livestock systems, ranging from extensive grazing, through integrated crop-livestock farming to intensive peri-urban &#39;industrial&#39; type production are considered. Relationships between these systems and key INRM issues facing farmers in each are highlighted. Results

Anthropogenic-induced water quality pollution is a
major environmental problem in freshwater ecosystems today.
As a result of this, eutrophication of lakes occurs. Population
and economic development are key drivers of water resource
pollution. To evaluate how growth in the riparian population
and in the gross domestic product (GDP) with unplanned
development affects the water quality of the lake, this paper
evaluates Lake Victoria Kenyan waters basin. Waters quality
data between 1990 and 2012 were analyzed along with reviews
of published literature, papers, and reports. The nitratenitrogen
(NO3-N), soluble phosphorus (PO4-P), chlorophyll a,
and Secchi transparencies were evaluated as they are key
water quality indicators. The NO3-N increased from
10 μg l−1 in 1990 to 98 μg 1−1 in 2008, while PO4-P increased
from 4 μg l−1 in 1990 to 57 μg l−1 in 2008. The population and
economic growth of Kenya are increasing with both having
minimums in 1990 of 24.143 million people and 12.18 billion
US dollars, to maximums in 2010 of 39.742 million people
and 32.163 billion US dollars, respectively. A Secchi transparency
is reducing with time, indicating an increasing pollution.
This was confirmed by an increase in aquatic vegetation
using an analysis of moderate resolution imaging
spectroradiometer (MODIS) images of 2000 and 2012 of
Kenyan waters. This study found that increasing population
and GDP increases pollution discharge thus polluting lakes.
One of major factors causing lake water pollution is the
unplanned or poor waste management policy and service.

Site-specific nutrient management (SSNM) is a plant-need-based approach for optimized application of nitrogen (N), phosphorus (P), and potassium (K) fertilizers. This study developed and evaluated SSNM recommendations for irrigated rice in Aklan, Antique, and Capiz during the crop year 2009-2010. Field trials using the nutrient omission plot technique provided information to calibrate Nutrient Manager for Rice, a computer-based decision tool. Additional field trials compared SSNM-based fertilizer recommendations of Nutrient Manager with farmer's fertilizer practices. Measured soil properties were not well related to rice yields measured in nutrient omission plots suggesting soil properties are not good predictors of nutrient supply in rice soils. Relationships of yield in nutrient omission plots with yield in full fertilized plots were comparable to relationships from other regions of the Philippines already used in Nutrient Manager. This provides confidence that Nutrient Manager is well adapted for Region 6. Fertilizer management based on Nutrient Manager increased yield by 370 kg per hectare per season. Results suggest an increased income of PhP 4500 per hectare per season is a realistic target with Nutrient Manager. When factors other than nutrients -such as pests, diseases, or poor crop management -limit rice yield, improved nutrient management should be combined with practices to overcome these constraints.

Western Kenya is one of Africa’s most densely populated rural areas, characterised by intensive smallholder crop–livestock systems on degraded lands managed with small inputs of mineral fertiliser and animal manure. Competing uses for crop residues and other organic resources often results in poor nutrient cycling efficiencies at farm scale. Modifying livestock feeding, retaining more crop residues in the field, and improving manure management can help conserving considerable amount of nutrients on-farm. To examine to what extent such strategies would be feasible, we analysed whole-farm nutrient cycling efficiencies (NCE) of a range of farms differing in resource-endowment and production orientation, identifying the most efficient farmer strategies considering labour and financial constraints. Nutrient concentration in excreted cattle manure was relatively small (i.e., N < 1.7%; P < 0.6%). Current manure management practices led to low NCE’s (average 27%) due to nutrient losses from excretion through storage and application. Farmers have few incentives to improve manure management given the small amounts of excreta and nutrients to be recycled. Yet, manure, both composted and fresh, represented the greatest N (16 kg ha−1 season−1) and C returns to the soil (312 kg C ha−1 season−1). Retention of crop residues was the cheapest source of nutrient inputs for the next crop, especially when compared with manure, but farmers prioritised its use for cattle feeding. Our findings highlight the critical lack of nutrients and organic residues on smallholder farms in the densely-populated highlands of East Africa, as well as low NCE when it comes to manure. In these conditions, efficient nutrient cycling for manure and improved cattle feeding are essential to increase use efficiencies of any possible external nutrient added in these farms.

Site-specific nutrient management (SSNM) provides a field-specific approach for dynamically applying nutrients to rice as and when needed. This approach advocates optimal use of indigenous nutrients originating from soil, plant residues, manures, and irrigation water. Fertilizers are then applied in a timely fashion to overcome the deficit in nutrients between the total demand by rice to achieve a yield target and the supply from indigenous sources. We estimated environmental impact of SSNM and evaluated economic benefits in farmers' fields in southern India, the Philippines, and southern Vietnam for two cropping seasons in 2002-2003. On-farm research comparing SSNM and the farmers' fertilizer practice showed increased yield with SSNM for the three locations, even with reduced fertilizer N rates in some 0308-521X/$ -see front matter Ó Agricultural Systems 93 AGRICULTURAL SYSTEMS cases. SSNM increased partial factor productivity (kg grain kg À1 fertilizer N) when fertilizer N use efficiency with the farmers' fertilizer practice was relatively low such as at locations in Vietnam and the Philippines. Use of on-farm data with the DNDC model revealed lower percentage of total N losses from applied fertilizers with SSNM during an annual cycle of cropping and fallows. At the location in India, SSNM showed the potential of obtaining higher yields with increased fertilizer N use while maintaining low N 2 O emissions. SSNM in the Philippines and Vietnam showed greater yields with less fertilizer N through improved fertilizer use efficiency, which could reduce N 2 O emissions and global warming. Use of SSNM never resulted in increased emissions of N 2 O per unit of grain yield, and in environments where higher yield could be obtained with less fertilizer N, the use of SSNM could result in reduced N 2 O emissions per unit of grain yield. For the economic analysis, data were generated through focus group discussions (FGD) with farmers practicing SSNM and with other farmers not practicing SSNM. Based on FGD, the seasonal increase in yield of farmers solely due to use of SSNM averaged 0.2 Mg ha À1 in southern Vietnam, 0.3 Mg ha À1 in the Philippines, and 0.8 Mg ha À1 in southern India. Farmers practicing SSNM at the study site in India used less pesticide. The added net annual benefit due to use of SSNM was 34 US$ ha À1 year À1 in Vietnam, 106 US$ ha À1 year À1 in the Philippines, and 168 US$ ha À1 year À1 in India. The increased benefit with SSNM was attributed to increased yield rather than reduced costs of inputs.

Most of the wastewater treatment systems in small rural communities of the Cova da Beira region (Portugal) consist of constructed wetlands (CW) with horizontal subsurface flow (HSSF). It is believed that those systems allow the compliance of discharge standards as well as the production of final effluents with suitability for reuse. Results obtained in a nine-month campaign in an HSSF bed pointed out that COD and TSS removal were lower than expected. A discrete sampling also showed that removal of TC, FC and HE was not enough to fulfill international irrigation goals. However, the bed had a very good response to variation of incoming nitrogen loads presenting high removal of nitrogen forms. A good correlation between mass load and mass removal rate was observed for BOD5, COD, TN, NH4-N, TP and TSS, which shows a satisfactory response of the bed to the variable incoming loads. The entrance of excessive loads of organic matter and solids contributed for the decrease of the effective volume for pollutant uptake and therefore, may have negatively influenced the treatment capability. Primary treatment should be improved in order to decrease the variation of incoming organic and solid loads and to improve the removal of COD, solids and pathogenic. The final effluent presented good physical–chemical quality to be reused for irrigation, which is the most likely application in the area.

CHINA Abbreviations and notes for this article: K= potassium; Cl = chloride; KCl = potassium c h l o r i d e ; K N O 3 = p o t a s s i u m n i t r a t e ; K 2 SO 4 = potassium sulfate; S = sulfur; Zn = zinc; Cu = copper; Ca =calcium; N = nitrogen; P = phosphorus; ASI = Agro Services International.

The experiment was conducted with the existing bearing trees of different jackfruit genotypes at Jamalpur region during the year 2014–2015. Twenty-three jackfruit germplasm viz., AHJ-01, AHJ-02, AHJ-03, AHJ-04, AHJ-05, AHJ-06, AHJ-07, AHJ-08, AHJ-09, AHJ-10, AHJ-11, AHJ-12, AHJ-13, AHJ-14, AHJ-15, AHJ-16, AHJ-17, AHJ-18, AHJ-19, AHJ-20, AHJ-21, AHJ-22 and AHJ-23 were selected for the study to identify superior ones. The recorded age of the selected tress ranged from 8 to 29 years. The selected superior genotypes differ widely among themselves. Great variability exists with regards to many desirable characters viz., bearing (once or twice a year), yield per tree (02–60 fruits per year), average fruit weight (2.57–11.00 kg), number of bulbs/flakes per fruit (41.00–181.00), number of seeds per fruit (39.00–180.00), total weight of bulbs (0.90–6.381 kg) and flake’s TSS (13–23%). Jackfruit trees are cross pollinated and are mostly seed propagated. As a result, morphological and agronomical characters of jackfruit showed a distinct range of variation. The quantitative data of jackfruit germplasm and their range, mean, standard deviation (SD), standard error (SE) and coefficient of variance (CV%) are presented. The highest quantitative variation was observed for total number of fruits per plant (CV 80.98%) which was followed by total bulbs weight (CV 56.02%) and weight of rachis (CV 49.64%). Minimum variation was noticed in seed breadth (CV 8.13%). A total of six qualitative characters were recorded and evaluated to the variability among the studied jackfruit germplasm. Wide range of variability regarding qualitative characters was observed among twenty-three jackfruit germplasm. Fruit skin colour, fruit shape, bulb colour, bulb firmness, sweetness & taste and seed colour of jackfruit germplasm were investigated. The maximum variation was observed in fruit skin colour and bulb firmness of jackfruit germplasm. Among the twenty-three jackfruit germplasms, one germplasm AHJ-02 showed early bearing habit (Off-season). So, the quantitative characters viz., age of plant 25 years, total number of fruits per plant 32 nos., weight of individual fruit 7.57 kg, date of harvest 05.03.2016, stalk attachment depressed, fruit length 33 cm, fruit breadth 22 cm, weight of rind 2.90 kg, weight of rachis 733 g, rind thickness 1.03 cm, total number of bulbs per fruit 288 nos., bulb length 4.29 cm, bulb breadth 1.93cm, 10-bulb weight 122.92 g, total bulb weight 3.54 kg, total number of seeds per fruit 284, seed length 2.56 cm, seed breadth 1.27 cm, 10-seed weight 34.01 g, total seed weight 966 g, edible portion 52% and TSS 23% were recorded. Qualitative characters viz. fruit colour-greenish yellow, fruit shape-oval, bulb colour-yellow, bulb firmness-medium soft, taste-sweet and seed colour-brownish patch in colour were recorded. Considering fruit characteristics i.e., taste, sweetness, hardness of bulb, bulb color, fruit size, %TSS, %edible portion and yield, the germplasm AHJ-02, AHJ-03, AHJ-04, AHJ-05, AHJ-06, AHJ-07, AHJ-09, AHJ-11, AHJ-14, AHJ-16, AHJ-18, AHJ-19, AHJ-21 and AHJ-23 were found to be suitable for jackfruit cultivation at Jamalpur region, Bangladesh. The present finding shows the great genetic potential of the studied germplasm. It can be used in future breeding programmes for getting productive and quality traits. Moreover, the variability observed in the current study could be used in jackfruit improvement programme. Finally, the plant breeders and horticulturists can choose germplasm according to their needs. Therefore, these jackfruit germplasms can be included in the variety development programme in future.

A Bayesian network consists of a graphical structure and a probabilistic description of the relationships among variables in a system. The graphical structure explicitly represents cause-and-effect assumptions that allow a complex causal chain linking actions to outcomes to be factored into an articulated series of conditional relationships. Each of these relationships can then be independently quantified using a submodel suitable for the type and scale of information available. This approach is particularly useful for ecological modelling because predictable patterns may emerge at a variety of scales, necessitating a multiplicity of model forms. As an example, we describe a Bayesian network integrating models of the various processes involved in eutrophication in the Neuse River estuary, North Carolina. These models were developed using a range of methods, including: process-based models statistically fit to long-term monitoring data, Bayesian hierarchical modelling of cross-system data gathered from the literature, multivariate regression modelling of mesocosm experiments, and judgements elicited from scientific experts. The ability of the network to accommodate such a diversity of methods allowed for the prediction of policy-relevant ecosystem attributes not normally included in models of eutrophication. All of the submodels in the network include estimates of predictive uncertainty in the form of probability distributions which are propagated to model endpoints. Predictions expressed as probabilities give stakeholders and decision-makers a realistic appraisal of the chances of achieving desired outcomes under alternative nutrient management strategies. In general, the further down the causal chain a variable was, the greater the predictive uncertainty. This suggests that a compromise is necessary between policy relevance and predictive precision, and that, to select defensible environmental management strategies, public officials must adopt decision-making methods that deal explicitly with scientific uncertainty.

Enhanced maize (Zea mays L.) production in Kabete sub-County, Kenya, is constrained by low soil fertility combined with continuous unsustainable agricultural practices. The current study evaluated the effects of incorporating dolichos (Lablab purpureus (L.) and combined fertilizer application on soil N, P and K balances, and maize yields in Kabete field station, University of Nairobi. The experiment was carried out, between mid-March to May 2015 (long rain season-LRS) and October to December 2015/16 (short rain season-SRS). The experimental set up was a Randomized Complete Block Design with a split-plot arrangement replicated three times. The main plots were; cropping systems i.e. incorporation of dolichos (i) as an intercrop (dolichos /maize intercrop) and (ii) in rotation with maize (dolichos-maize rotation). Sole maize, without dolichos integration, was included as control. The sub-plots were fertilizer types: (i) farmyard manure (FYM); (ii) triple superphosphate (TSP) and urea; (iii) integrated organic and organic fertilizer (FYM+TSP+Urea) and (iv) no fertilizer applied (control). Top soil samples (0-20 cm) were taken at the end of each cropping season, for determination of total N and available P and K. The NUTrient MONitoring (NUTMON/ MonQi,) tool box was used to calculate N, P and K balances. Maize was harvested at physiological maturity for yield determination. Significantly (P≤0.05) high soil N and P levels were obtained in maize/dolichos intercrop with application of FYM and TSP+FYM+Urea in both LRS (0.29% and 19.6 ppm; 0.3% and 16.5 ppm) and SRS (0.34% and 28.5 ppm; 0.28% and 26.1 ppm), respectively. The soil K (cmol/Kg) levels were significantly (P≤0.05) high in maize/dolichos intercrop with FYM application during the SRS (1.3) and LRS (1.8). Less negative N balances (-9.1 kg ha-1 yr-1) were obtained in maize/dolichos intercrop with FYM application while pronounced N (-20.1 kg ha-1 yr-1) losses were realized in maize/dolichos intercrop with TSP+Urea application. P losses were higher in maize/dolichos with TSP+FYM+Urea (-2.2 kg ha-1 yr-1) and TSP+Urea (-2.4 kg ha-1 yr-1) application. Significantly (P<0.5) higher K losses (kg ha-1 yr-1), with TSP+Urea application, occurred in dolichos/maize intercrop (-6.7), dolichos-maize rotation (-4.9) and in sole maize (-4.5). Maize grain yields (t ha-1) in the SRS and LRS were significantly (P≤0.05) higher in dolichos/maize intercrop with application of TSP+FYM+Urea (5.6 and 4.5) and FYM (5.4 and 4.9) with no significant differences across seasons. Dolichos-maize rotation with TSP+FYM+Urea application resulted in significantly higher dry matter yields (9.4 t ha-1) compared to intercrop with FYM (9.5 t ha-1) application in the SRS. When compared across seasons, soil NPK levels, maize grain and dry matter yields were consistently higher in maize/dolichos intercrop with application of FYM and TSP+FYM+Urea in the SRS compared to LRS. Pronounced negative N and P balances were realized in maize/dolichos intercrop and dolichos-maize rotation with application of FYM and TSP+FYM+Urea. It is evident that improved soil nutrient status led into increased maize yields. With the increase in maize yields, however, significant nutrient losses were realized. Adoption of the best performing technology, incorporation of dolichos in maize as an intercrop with application of FYM and TSP+Urea, ought therefore to be tapered (in the short run) with prudent nutrient management strategies to minimize nutrient losses through harvested products for cropping system sustainability.

The looming water crisis and water-intensive nature of rice cultivation are driving the search for alternative management methods to increase water productivity in rice cultivation. Experiments were conducted under on-station and on-farm conditions to compare rice production using modified methods of irrigation, planting, weeding and nutrient management with conventional methods of cultivation. Farm surveys were used to evaluate adoption of modified rice cultivation method. On-station experiments showed that, a combination of water-saving irrigation, young seedling or direct seeding, mechanical weeding and green manure application increased the rice water productivity though the largest yields were obtained for a combination of conventional irrigation, young seedling or direct seeding, mechanical weeding and green manure application. On-farm experiments demonstrated a yield advantage of 1.5 t ha−1 for the modified method over conventional method. We found, however, that yield advantages were not the sole factor driving adoption. Associated changes required in management, including the increased labour demand for modified planting, unwillingness of agricultural labourers to change practices, difficulties with modified nursery preparation and the need to replace cheaper women’s labour for hand weeding with more costly men’s labour for mechanical weeding, all reduced the chance of adopting the modified rice cultivation method. Risks associated with water-saving irrigation, such as uncertainty about the timing and amount of water release for irrigation affect adoption adversely as well. There was no incentive for farmers to adopt water-saving irrigation as water from reservoirs and electricity for pumping well-water are both free of charge. To date farmers continue to experiment with the modified cultivation method on a small part of their farms, but are unlikely to adopt the modified method on a large-scale unless policies governing water management are changed.

Sodic and alkali soils are characterized by the occurrence of excess sodium (Na + ) to levels that can adversely affect soil structure and disturb the availability of nutrients for plant growth. Structural problems in these soils are created by certain physical processes (slaking, swelling and dispersion of clay minerals) and specific conditions (surface crusting and hardsetting), which affect water and air movement, seedling emergence, root penetration, runoff and erosion, as well as tillage and sowing operations. Such changes ultimately impact choice of crops, and crop growth and yield, which are also affected by osmotic and ion-specific effects in these soils. Of the salt-affected soils worldwide, about 60% are sodic and alkali soils, warranting attention for efficient, inexpensive and environmentally feasible amelioration. Sodic and alkali soil amelioration primarily involves increasing calcium (Ca 2+ ) on the cation exchange complex at the expense of Na + . The replaced Na + is removed from the root zone through infiltrating water resulting from excessive irrigation(s). Several approaches aiming at amelioration of these soils have been used, which include application of water, crop, chemical amendment, electric current and tillage as amelioration tools. In addition, management of plant nutrient elements in these soils has been addressed as a crucial factor in improving crop productivity and soil fertility. While the principles and technologies aiming at the amelioration of sodic and alkali soils are fairly well understood, their adoption in poor and developing countries is very slow because the majority of the affected lands are in the possession of resource-poor communities or form part of the common property resources of the villages. This paper reviews various amelioration and nutrient management approaches as well as constraints to large-scale adoption of the amelioration approaches. This information will assist researchers and farm advisers in choosing appropriate management practices to achieve maximum benefits from these soils while considering the participation of the farmers in the planning and setting of the amelioration programmes.

Some 60% of coastal rivers and bays in the U.S. have been moderately to severely degraded by nutrient pollution. Both nitrogen (N) and phosphorus (P) contribute to the problem, although for most coastal systems N additions cause more damage. Globally, human activity has increased the flux of N and P from land to the oceans by 2-fold and 3-fold, respectively.

A mathematical model is developed to determine the optimum rate of mixed fertilizer as well as the rate of leaves fertilizer to produce quality pineapples. Regressional method using Excel and LINDO optimizer software were used in the application of the model. It is found that the combination of fertilizer for nitrogen 75.00 kg/ha, phosporus 57.00 kg/ha and potassium 89.00 kg/ha produces a high yield of pineapple and the objective to minimize fertilizer cost is fully achieved.

Makanan sebagai sumber protein, karbohidrat, lemak, vitamin, dan mineral sangat diperlukan bagi kesehatan fisik, pertumbuhan, dan mengatur proses metabolisme. Makanan yang berkualitas, aman dan menarik dapat diperoleh melalui perlakuan yang tepat pada setiap tahapan produksi, mulai dari persiapan, pengolahan, penyimpanan, pemasaran dan penggunaannya. Makanan yang tidak aman jika dikonsumsi dapat menimbulkan gangguan kesehatan bahkan berakibat pada kematian (Suryana, 1994, dalam Sundari, 2013). Undang-undang Nomor 7 Tahun 1996 menyatakan bahwa kualitas pangan yang dikonsumsi harus memenuhi beberapa kriteria, diantaranya adalah aman, bergizi, bermutu, dan dapat dijangkau oleh daya beli masyarakat. Aman maksudnya mencakup bebas dari cemaran biologis, mikrobiologi, kimia, logam berat, dan cemaran lain yang dapat mengganggu, merugikan dan membahayakan kesehatan manusia (Mudjajanto, 2014). Dalam Islam dikenal dengan istilah makanan halalan thayyiban. Makanan halalan (halal) yaitu makanan yang tidak diharamkan, dan tidak menyalahi hukum syari`at Islam untuk dikonsumsi sesuai Al-Qur'an dan sunnah nabi. Makanan yang baik atau dalam istilah agama thayyiban yaitu baik dari sudut pemenuhan kebutuhan gizi bagi tubuh, pengolahan makanan baik, dan bahan campuran yang baik. Saat ini, Industri pangan di Indonesia telah berkembang dengan pesat, ditandai dengan munculnya industri kecil dan industri rumah tangga yang 1

Submerged constructed wetlands with sub-surface horizontal flow are suitable systems for wastewater treatment and reuse in small communities. Laboratory studies are a useful way to better understand the evolution of pollutant removal mechanisms
throughout the system. Two Series of experiments were performed in a laboratory microcosms system colonized by Phragmites australis, at the hydraulic loading of 1.67x10-3 m3 m-2 h-1 (approximately 4 cm d-1), organic loading ranging from 10 to 23.4 g m-2 d-1 COD, ammonia nitrogen loading ranging from 1 to 2 g m-2 d-1 NH4-N,
C/NH4-N ratio of 4 and hydraulic retention time of 4.6 d.
The results show an improvement of organic matter and ammonia nitrogen removals rates over time with average values of 7.2 g m-2 d-1 COD and 0.5 g m-2 d-1NH4-N, respectively, a considerable development of the plants and a good adaptation of the biofilm to changes in incoming loading conditions. The higher values of both
removal rates occurred in the initial bed section where the superior DO concentrations allowed the occurrence of aerobic pathways. In the remaining sections (approximately 1.7 m length) the system was DO limiting and the organic removal occurred at lower rates, which seemed to be associated with the prevalence of anaerobic pathways. Although nitrification appears as the most important mechanism of ammonia nitrogen removal, no significant concentration of nitrate nitrogen was detected along the bed, which may be explained by the quick removal of this compound by denitrification. For the range of applied organic and ammonia loadings there was no evidence of a significant variation of the global organic removal rate or the nitrification rate when the incoming characteristics where changed. However, the
nitrification rate at the initial section was in fact affected by changing on incoming loading conditions.

Maize is an important crop for food and nutritional security in India. Strong market demand and resilience of maize to abiotic and biotic stresses have increased the area and production of maize in the country over the past decade. Productivity of maize, however, has not increased proportionately and significant yield gaps are evident across maize growing areas in the country. Maize is an exhaustive crop and removes large amounts of plant nutrients from the soil to support high biomass production. The 4R Principles of applying right source of nutrients, at the right rate, at the right time and at the right place is expected to increase nutrient use efficiency, productivity and farm profit from maize production and provides opportunity for better environmental stewardship of nutrients. Adaptation of 4R Principle-based site-specific nutrient management decision support tools provides the opportunity for large-scale adoption of improved nutrient management across maize ecologies. Indian J. Fert., Vol. 9 (4), pp.80-94 (15 pages)

The significant higher growth, seed cotton yield and yield attributes were obtained with the
application of 100 per cent RD of nitrogen and phosphorus. Among the tested doses of fertilizers 100 per
cent RD of phosphorus and nitrogen recorded significantly higher yield (3849 kg/ha) and (3723 kg/ha),
respectively over 75 per cent RD. However, the further increase in nitrogen and phosphorus doses had no
significant increase in seed cotton yield. Significantly higher bolls/plant (52.1 and 51.0) was obtained with
100 per cent RD of phosphorus and nitrogen, respectively. The seed cotton yield of Bt cotton increased to
the tune of 17.22 and 16.42 per cent with the application of 100 per cent RD of nitrogen and phosphorus,
respectively as compared to 75 per cent RD of each nutrient.