Inorganic Chemical Fertilizers Research Articles

Nitrogen Budget of South Korea from 2015 to 2019 Including Gaseous Nitrogen Oxides

Objectives : The study was aimed to systematically understand the nitrogen budget from 2015 to 2019, and to determine the annual nitrogen balance in South Korea.Methods : The nitrogen budget was calculated by classifying into agricultural and livestock, city, and forest areas. The nitrogen input was estimated from deposition, biological fixation, agricultural water, inorganic chemical fertilizer, compost, feedstuff, produced crops, imported grocery, and fuel consumption. The nitrogen output was estimated by considering denitrification, volatilization, ground water runoff, land and crop absorption, sewage disposal, drainage, forest uptake, and nitrogen oxide (NOx) emissions.Results and Discussion : The annual nitrogen budget from 2015 to 2019 showed the input as 6,107,449 ton/yr, 6,144,666 ton/yr, 6,245,240 ton/yr, 6,281,552 ton/yr, 5,993,347 ton/yr and the output as 1,346,587 ton/yr, 1,369,119 ton/yr, 1,365,327 ton/yr, 1,378,940 ton/yr, 1,365,994 ton/yr, respectively. The NOx, highly contributing to change in the nitrogen budget, was caused by human activities such as vehicles, business places, and power plants. More than 32% of the total nitrogen budget was caused by NOx in every year.Conclusion : The nitrogen budget continued to increase in the 2010s because of the increase in food and fuel consumption by urbanization. However, the nitrogen budget declined in 2019 due to the effort such as emission regulations and the use of alternatives as the awareness of environmental pollution gradually increased. Therefore, the appropriate institution should be established and actively implemented to reduce the nitrogen effectively.

Inorganic Comparison of Inorganic Element Detection Technology in Soil

Soil pollutants include inorganic substances (heavy metals, acid, salt, etc.), organic matter, chemical fertilizers, pesticides (pesticides, sterilizers and herbicides), radioactive substances, parasites, pathogenic bacteria, and viruses. New pollutants (such as veterinary drugs, antibiotics, bromide flame retardants, all -fluoride compounds, etc.) have also become research hotspots in the soil.

Nanofertilizers as an alternative to inorganic fertilizers: A review

The population of the world is steadily increasing, in contrast to the natural resources which are limited and subjected to further depletion. This induces pressures to develop effective agricultural production systems to meet the growing demands on food and, thus, to mitigate hunger and poverty worldwide. Generally, inorganic fertilizers play a crucial role in maintaining soil fertility and improving crop yield and quality. Inorganic chemical fertilizers are regarded as the main source to supply crops with their needs of nutrients. Proper nutrient management of crops is a major challenge worldwide as it relies predominantly on chemical fertilizers. However, inorganic fertilizers are not only costly but may be harmful and pose risks to human health and have negative impacts on the environment. About half of the amount of applied fertilizers is used by the crop, whereas the remaining fertilizers are lost through leaching and gaseous emissions. The lost nutrients contribute to environmental pollution, global warming and climate change. Moreover, high application rates of chemical fertilizers can deteriorate soil fertility and raise soil salinity and thus lower crop production and quality will occur. This creates a need to invent smart fertilizers that are friendly to the environment, particularly those of high nutrient use efficiency and low leaching potential. Nanotechnology has a vital role in the construction of such fertilizers (nanofertlizers). In these fertilizers, nutrients are bound to nano-dimensional adsorbents (nanomaterials), which release nutrients very slowly as compared to conventional chemical fertilizers. Nanofertilizers are nutrients coated or encapsulated with different types of nanomaterials. They have unique properties like large surface area, slow-release profile, and controlled delivery of nutrients to the targeted sites to meet the nutrient requirements of crops. Nanofertilizers are emerging as a promising alternative to conventional chemical fertilizers, as they offer great opportunities to improve plant nutrition under harsh environments. The benefits associated with the use of nanofertlizers are opening new approaches toward the development of sustainable agriculture. However, further studies are needed for a sound and safe application of nanofertlizers. In this review, researchers’ attempts to produce and use nanofertlizers for sustainable crop production have been presented. The advantages and limitations of the application of these smart fertilizers have also been discussed. Key words: Nanoparticles, Sustainable agriculture, Phytotoxicity, Slow and controlled release, Metal oxides

Soil test-based fertilizer prescription for targeted yield of sesame (Sesamum Indicum L.)

ABSTRACT To develop targeted yield-based integrated nutrient recommendation of sesame, soil test-based crop response field studies on major nutrients were undertaken during two consecutive seasons (2016 and 2017) in an Inceptisol. For this, quantitative estimations of basic parameters viz. nutrient requirement (NR), percentage contribution of nutrients from soil (CS); from fertilizer (CF); from farm yard manure (CFYM) were done. The essential informations obtained from soil and crop testing were used for development of fertilizer prescription equations for different nutrient management practices using organic (FYM) and inorganic chemical fertilizer alone or in combinations. The mean nutrient requirement for the production of 100 kg of sesame grain was 6.98, 1.61 and 3.92 kg of nitrogen (N), phosphorus (P) and potassium (K), respectively. The CS, CF and CFYM values were 21.84, 49.35 and 6.95 for N; 40.23, 26.25 and 4.57 for P; 12.80, 53.13 and 4.07 for K, respectively. Those parameters were used for preparation of ready reckoners of fertilizer prescription for range of soil test values of N, P and K to get targeted yield (±5 to ±10% of potential yield of variety) of 9 q/ha for sesame grain using FYM and inorganic chemical fertilizer alone or in combinations. Amount of N, P and K fertilizer could be reduced by a significant amount if fertilizers were applied on soil test basis in integration with FYM.

Divergent soil health responses to long-term inorganic and organic fertilization management on subtropical upland red soil in China

To optimize soil health, land use, and soil management decisions need to be guided by an understanding of the underlying soil health. Although widely used fertilizers guarantee crop production, they ultimately damage agricultural soil environmental quality and threaten the overall food chain safety. Thus, an integrative assessment considering both environmental safety and soil fertility is required for the sustainable development of long-term fertilization systems. In this study, we conducted a comprehensive assessment of soil health using 20 soil physical, chemical, and biological indicators and assessed them according to four heavy metals—copper, zinc, cadmium, and lead. This experiment was conducted in an area where there is an ongoing, 23-year-long fertilization experiment in a typical red soil region of southern China, including four treatments of common inorganic chemical fertilizer (CF), CF mixed with micronutrients (CF + T), CF mixed with pig manure (PM), and PM mixed with micronutrients (PM + T). To assess the soil fertility quality, we selected a minimum data set consisting of soil water-stable aggregates mean weight diameter, available phosphorus, total nitrogen, microbial biomass carbon, and dehydrogenase activity. The results revealed that soil fertility quality followed the order of PM + T ≈ PM > CF + T > CF. We also used a modified potential ecological risk index to assess the soil environmental quality. This approach considered the acid-soluble and exchangeable fraction of heavy metals as the bioavailability component. Both PM and PM + T treated soils were significantly contaminated by heavy metals, with particularly large amounts of Cd contamination. The soil health index escalated from CF, CF + T, PM to PM + T, which indicated that the use of pig manure allowed for more fertile soil relative to standard chemical fertilization. Moreover, applying additional micronutrients also had a significant influence on soil fertility. Therefore, our study revealed that long-term fertilization using organic pig manure was beneficial to overall soil fertility; however, these benefits were coupled with significant limitations regarding heavy metal contamination. Collectively, this study provides a better supporting method for soil health management and long-term fertilization strategies.

Utilization of Eco-Enzyme from Household Organic Waste to Maintain Soil Fertility and Plant Pest Control

The use of inorganic chemical fertilizers and synthetic pesticides in the cultivation of crops carried out by farmers has caused negative effects on the environment. Likewise, the disposal of household organic garbage by the community has caused pollution in the surrounding environment. To reduce environmental disturbances due to garbage deposits, household organic garbage can be utilized for making eco-enzyme. Eco-enzyme is a complex organic compounds solution resulting from the fermentation of organic garbage, water, and sugar. Eco-enzyme solution can be used by the community as a versatile cleaning liquid, for environmentally friendly plant fertilizer and plant pest control. Community service activity has been carried out in Gelebak Dalam Village, Rambutan District, Banyuasin Regency, in the form of counseling and demonstrations of making eco-enzyme solutions from fruit peels and vegetable residues. Knowledge of eco-enzyme is very beneficial for the community, because, in addition to reducing the negative effects of organic garbage deposits on the environment, eco-enzyme is also useful in reducing the use of inorganic fertilizers and synthetic pesticides in plant cultivation activities.

Effect of Phosphorus in Conjoint with Organics and Bioinoculant on Growth, Yield and Quality Parameters of Blackgram in Typic Chromustert

Aims: Use of phosphorus fertilizer along with farmyard manure, vermicompost and phosphorus solubilizing bacteria (Bacillus megaterium) in black calcareous soil was conducted to assess the impact on the growth, yield and quality parameters of blackgram variety VBN 8 during the year 2022.
 Study Design: Randomized Block Design (RBD) with twelve treatments and three replications.
 Place and Duration of Study: Kalligudi block of Madurai district, representing the Southern part of Tamil Nadu during the summer season of 2022.
 Methodology: Twelve treatments were followed with various combinations of organics viz, vermicompost and farmyard manure, bioinoculant, and inorganic chemical fertilizer at different ratios. The combinations are 100 per cent and 75 per cent of P2O5 on STCR (Soil Test Crop Response) basis mixed with farmyard manure (1:10 ratio) and vermicompost (1:5 ratio). The impact of different treatments were recorded on shoot length, root volume, SPAD value, Leaf Area Index, grain yield, protein, cystine, and methionine content.
 Results: Among the treatments, application of 100% of P2O5 on Soil Test Crop Response (STCR) basis incubated for 30 days with vermicompost at 1:5 ratio + phosphorus solubilizing bacteria @ 2 kg ha-1 T11 has improved the black gram shoot length (27.6 cm), root volume (2.43 cm3), SPAD value (45.91), Leaf Area Index at 20 DAS (1.09) and 40 DAS (3.7), grain yield (936.1 kg ha-1) protein content (23.21%), cystine content (1.97%) and methionine content (2.29%).
 Conclusion: The integration of vermicompost and bioinoculant along with phosphorus fertilizer in black calcareous soil has improved the blackgram yield by 35.8% over the use of recommended dose of fertilizer alone. This result highlights the need of integrated application of phosphorus fertilizer along with organics and phosphorus solubilizing bacteria in black calcareous soil for sustainable production of blackgram.

The Effect of Urea Dosage Levels on Vegetative Growth of Some Clones Robusta Coffee (Coffea Canephora)

Coffee plants are one of the important commodities that have a fairly high selling value. Indonesia is one of the largest coffee producing countries in the world with a production of approximately 600,000 tons per year. The application of inorganic (chemical) fertilizers is very important if coffee plants are cultivated on soils that naturally have low fertility. In addition to the level of soil fertility as well, the purity of the planting material must be known from its origin. Because to get optimal results, a superior type or clone of coffee is also needed. This research was conducted at the Lampung State Polytechnic Plantation Plant Entres Garden which is located in Hajimena Village, Natar District, South Lampung Regency with a garden height of 118 m above sea level. This research was carried out in June-October 2021. This study was compiled using a Split Plot Design. Coffee clones were assigned to the main plot and the urea fertilizer dose factor was assigned to subplots. Observational data that has been obtained will be analyzed using analysis of variance (F test) at the 5% level. If there is a significant difference (F count > F table 5%), it will be continued with the Least Significant Difference (LSD) follow-up test with a level of 5%. Based on the results and discussions that have been obtained, it shows that the administration of urea to several Robusta coffee clones gave a significant interaction with the parameters of plant height and stem diameter and clones BP 358 with urea doses of 15 and 20 g gave the best growth compared to other clones.

Linking Soil Microbial Diversity to Modern Agriculture Practices: A Review.

Agriculture is a multifarious interface between plants and associated microorganisms. In contemporary agriculture, emphasis is being given to environmentally friendly approaches, particularly in developing countries, to enhance sustainability of the system with the least negative effects on produce quality and quantity. Modern agricultural practices such as extensive tillage, the use of harmful agrochemicals, mono-cropping, etc. have been found to influence soil microbial community structure and soil sustainability. On the other hand, the question of feeding the ever-growing global population while ensuring system sustainability largely remains unanswered. Agriculturally important microorganisms are envisaged to play important roles in various measures to raise a healthy and remunerative crop, including integrated nutrient management, as well as disease and pest management to cut down agrochemicals without compromising the agricultural production. These beneficial microorganisms seem to have every potential to provide an alternative opportunity to overcome the ill effects of various components of traditional agriculture being practiced by and large. Despite an increased awareness of the importance of organically produced food, farmers in developing countries still tend to apply inorganic chemical fertilizers and toxic chemical pesticides beyond the recommended doses. Nutrient uptake enhancement, biocontrol of pests and diseases using microbial inoculants may replace/reduce agrochemicals in agricultural production system. The present review aims to examine and discuss the shift in microbial population structure due to current agricultural practices and focuses on the development of a sustainable agricultural system employing the tremendous untapped potential of the microbial world.

Bacillus cereus Improves Performance of Brazilian Green Dwarf Coconut Palms Seedlings With Reduced Chemical Fertilization.

Coconut production in the Amazon requires the knowledge and development of sustainable technologies to alleviate the detrimental effects of inorganic chemical fertilizers and intensive farming practices. In this study, we investigated the effects of plant growth-promoting rhizobacteria (PGPR) isolated from coconut seedlings on nutrient use efficiency (NUE) and physiological mechanisms related to biomass accumulation of seedlings grown with reduced inorganic fertilizer levels. Of the 96 PGPR isolates tested on rice plants, the isolate Bacillus cereus (UFRABC40) was selected, as it resulted in the most significant gain in growth variables. In a commercial coconut tree nursery, we subjected seedlings to two treatments, both with seven replications: control 100% NPK chemical fertilizer (CF) and B. cereus + 50% NPK CF. The results indicated that the inoculation increased phytohormone levels [190% indole acetic acid (IAA), 31% gibberellic acid GA3, and 17% gibberellic acid GA4] and leaf gas exchange [48% by assimilation of CO2 (A), 35% stomatal conductance to water vapor (gs), 33% transpiration, and 57% instantaneous carboxylation efficiency] in leaves. Furthermore, growth parameters (shoot, root, and total dry weight, height, and diameter) and macro- and micronutrient levels (95% N, 44% P, 92% K, 103 Ca, 46% Fe, 84% B) were improved. Our results show the potential ability of strain Bacillus cereus UFRABC40 to promote the growth performance of coconut seedlings under decreased application of inorganic fertilizers. The application of microbial-based products in coconut seedling production systems improves plants’ physiological performance and the efficiency of nutrient use.

Studies on the effect of PGPR on the growth and yield of tomato (Lycopersicon esculentum) var. PKM-1

Tomato is one of the most popular and widely grown vegetables in the world, ranking second importance next to potato in many countries. Due to the high usage of N and P inorganic chemical fertilizers in agriculture leads to pollution, acidification of soils and emission of greenhouse gases cause economic and environmental losses. In the present study, isolation and characterization of rhizobacteria such as Pseudomonas sp., Azospirillum sp. and Azotobacter sp. were exanimated from different soils of Cuddalore district of Tamil Nadu. The effect of eight combination treatments of biofertilizers were tested on tomato plant growth and development in pot culture. The results, Pseudomonas sp. was found as highest colony forming unit (6.5×106/g) in Sivapuri village followed by Azotobacter (5.1×106/g) and Azospirillum sp. (4.3×105/g). The highest plant height at different days (25, 50, 75 and 100th) was found (22.34 cm, 41.71 cm, 65.27 cm and 85.36 cm) with the combination of treatment T8 (Ps+Azo+Azs) and the highest number of fruits per plant, fruit weight and yield were found in the treatment T8 (Ps+Azo+Azs) such as 26 (fruits/plant), fruit weight 40.95 (g/fruit) and yield 1040 (g/plant). All the results were found highest compared with control.

Integrated Nutrient Management (INM) in Soil and Sustainable Agriculture

The world vision of no hunger target, food security, and zero poverty followed by raising standards of living of rural people through agricultural transformation is the greatest challenges faced by the agricultural planners worldwide. Due to the alarming state of population growth and cultivable land scarcity, change in agronomic practices which could bring a significant effect on crop production and productivity is urgently needed. The concept of using different sources of plant nutrients combined to check nutrient depletion, maintain soil health, and crop productivity, called INM, has a bright solution in this area. Recently several researchers introduced that integrated use of inorganic fertilizers, organic fertilizers, green manure, and bio-fertilizers is becoming an effective practice not only for increasing crop production and productivity but also for the better crop and soil health. In addition, INM helps to increase the activity of soil microorganisms and improves the soil physical, chemical and biological properties. So, INM create an economic eco-friendly environment by reducing the dependence on inorganic chemical fertilizers and improving the soil fertility, optimizing crop yield, maximizing profitability and ultimately making the agriculture sustainable. Lastly, INM is one of the good agricultural practices which needs to be followed by every conscious individual in order to maintain soil health, nutrient balance and to make the agriculture and environment more sustainable. Int. J. Appl. Sci. Biotechnol. Vol 9(3): 160-165

Effect of fertilization on nitrogen losses through surface runoffs in Chinese farmlands: A meta-analysis

Surface runoff is the main cause of farmland nitrogen (N) losses in plain areas, which adversely affect water quality. The impact of fertilization on N runoff loss often varies. A meta-analysis was performed using 245 observations from 31 studies in China, to estimate the response of N loss in both paddy and upland fields subjected to different fertilization strategies, and investigate the link between N runoffs, soil properties, as well as precipitation in the planting season. The results showed that compared to the control (without fertilization), N losses subjected to fertilization increased from 3.31 kg/ha to 10.03 kg/ha and from 3.00 kg/ha to 11.24 kg/ha in paddy and upland fields respectively. Importantly, paddy N loss was significantly correlated with fertilizer type and N application rate (predictors); in upland fields N application rate and seasonal precipitation were the main driving factors. For the N application rate, N loss increased with increase in rates for both paddies and upland fields. Moreover, the N loss from upland fields increased with the precipitation during planting season. Between the three fertilizers used in paddies, the increase in loss of CRF (controlled release fertilizer) or OF (organic fertilizer) was lower than that of CF (inorganic chemical fertilizer) with the lowest value in CRF. Subset analysis showed that the effect of CRF and OF in paddies was not affected by the predictors, revealing the steadily controlling property of CRF and OF in paddies. Also, all the predictors had an insignificant impact to N loss risk in paddies during the high application rate. Overall, the results confirm the importance of N dosage in N runoff loss from farmland. Fertilizer type is a key consideration for N loss control in paddies, while the seasonal precipitation should not be ignored in upland fields.

Unlocking employee’s green behavior in fertilizer industry: the role of green HRM practices and psychological ownership

The engineering of agrochemicals and inorganic fertilizers indirectly facilitates the emissions of NO2 and CO2. The extensive use of pesticides and inorganic chemical fertilizers has drawn the world’s attention to green practices. Grounded on the ability-motivation-opportunity (AMO) theory, we investigated the effect of green human resource management (GHRM) practices on employees’ green behavior with the mediating role of psychological ownership. We applied the partial least square structural equation modeling (PLS-SEM) technique to 279 responses acquired from the fertilizer manufacturing firm employees. The results show that GHRM practices (green competence building, green motivation enhancing, and green employee involvement practices) significantly improve employee green behavior. Additionally, GHRM practices enhance the sense of ownership of nature among employees due to which they involve themselves proactively in eco-friendly activities and behavior.

Inorganic Chemical Fertilizer Application to Wheat Reduces the Abundance of Putative Plant Growth-Promoting Rhizobacteria.

The profound negative effect of inorganic chemical fertilizer application on rhizobacterial diversity has been well documented using 16S rRNA gene amplicon sequencing and predictive metagenomics. We aimed to measure the function and relative abundance of readily culturable putative plant growth-promoting rhizobacterial (PGPR) isolates from wheat root soil samples under contrasting inorganic fertilization regimes. We hypothesized that putative PGPR abundance will be reduced in fertilized relative to unfertilized samples. Triticum aestivum cv. Cadenza seeds were sown in a nutrient depleted agricultural soil in pots treated with and without Osmocote® fertilizer containing nitrogen-phosphorous-potassium (NPK). Rhizosphere and rhizoplane samples were collected at flowering stage (10 weeks) and analyzed by culture-independent (CI) amplicon sequence variant (ASV) analysis of rhizobacterial DNA as well as culture-dependent (CD) techniques. Rhizosphere and rhizoplane derived microbiota culture collections were tested for plant growth-promoting traits using functional bioassays. In general, fertilizer addition decreased the proportion of nutrient-solubilizing bacteria (nitrate, phosphate, potassium, iron, and zinc) isolated from rhizocompartments in wheat whereas salt tolerant bacteria were not affected. A “PGPR” database was created from isolate 16S rRNA gene sequences against which total amplified 16S rRNA soil DNA was searched, identifying 1.52% of total community ASVs as culturable PGPR isolates. Bioassays identified a higher proportion of PGPR in non-fertilized samples [rhizosphere (49%) and rhizoplane (91%)] compared to fertilized samples [rhizosphere (21%) and rhizoplane (19%)] which constituted approximately 1.95 and 1.25% in non-fertilized and fertilized total community DNA, respectively. The analyses of 16S rRNA genes and deduced functional profiles provide an in-depth understanding of the responses of bacterial communities to fertilizer; our study suggests that rhizobacteria that potentially benefit plants by mobilizing insoluble nutrients in soil are reduced by chemical fertilizer addition. This knowledge will benefit the development of more targeted biofertilization strategies.

Physical deterioration of soil and rice productivity in rural Java

Soil degradation is one of the world’s most serious ecological and environmental problems affected agricultural productions. The agricultural sector defines land degradation as a process of decreasing land productivity that is temporary or permanent, characterized by a decrease in physical, chemical, and biological properties. This study aims to investigate the impact physical deterioration of which occurs in the form of structure fertilizer application on rice productivity. This study applied Autoregressive model to analyse the primary data collected from 4 main rice producer areas in Central Java and East Java, namely Cilacap, Grobogan, Lamongan and Jember. The results show that previous chemical fertilizer use has negative impacts on rice productivity. Inorganic chemical fertilizers have an important role in increasing productivity, but at the same time the uncontrolled use of it is one of the causes of the decline in the quality of biological, physical, and chemical fertility of the soil.

The Effect of Integrated Organic and Inorganic Fertilizer on Soil Fertility and Productivity

Soil fertility depletion is a main problem to sustain agricultural production and productivity in many countries. The use of inorganic (chemical) fertilizer or organic fertilizer alone has both positive and negative effects on plant growth, nutrient availability and the soil. Inorganic fertilizer is usually immediately and fast containing all necessary nutrients that are directly easy to get for plants. But continuous use of inorganic (chemical) fertilizers alone causes soil organic matter degradation, soil acidity and environmental pollution. However, Organic fertilizer improves physical and biological activities of soil, but comparatively organic fertilizers has lower nutrient content, because of that larger quantity of fertilizer is required to adequate nutrient for plant growth. So integrated or mixed inorganic and organic nutrient management system is an alternative system for the sustainable and cost effective management of soil, and the result is raising soil fertility and productivity without affecting environment. The objective of the review is to assess the effect of mixing organic with inorganic fertilizer on soil fertility and productivity. The study revealed that appropriate application of organic with inorganic fertilizers increases the productivity without negative effect on productivity and improves soil fertility than the values obtained by organic or inorganic fertilizers separately.

A Comparative Assessment of Trace Element Accumulation in Native and Improved Rice (Oryza sativa L.) Varieties Grown Under Different Conditions of Fertilizer Application.

Rice (Oryza sativa L.) is the main food crop cultivated in Sri Lanka, and different varieties of rice are grown under different conditions of fertilizer application throughout the country. Since the consumption of rice is extremely high, it is considered as the major dietary source for macro- and micro-nutrients and also for toxic trace elements. The main objective of this study was to investigate and compare trace element levels in native and improved rice varieties that were grown under both organic and inorganic chemical fertilizers and also under unfertilized conditions. Rice grains were collected from a plot experiment with seven native and seven improved rice varieties that were treated with organic and inorganic fertilizers. Contents of macro-nutrients (Na, K, Ca and Mg) and trace elements (Cd, As, Pb, Cr, Mn, Co, Ni, Cu, Zn and Ba) in rice grains were measured by inductively coupled plasma mass spectrometry. The results indicated that rice cultivated using inorganic fertilizers showed the highest mean trace element contents while organic fertilizer-treated improved rice varieties showed the lowest Cd (0.10mg/kg) which is lower than the maximum permissible level (0.2μgg-1). The highest mean value of Cd (0.32mg/kg) was recorded in native rice varieties grown in plots with chemical fertilizer applications. However, the As content in rice samples collected from all treatment conditions indicated contents lower than the maximum permissible level. Rice cultivated in plots that were treated with chemical fertilizer showed the highest mean macro-nutrient contents.

Impact of green revolution on rice cultivation practices and production system: A case study in Sindang Hamlet, Rancakalong Village, Sumedang District, West Java, Indonesia

Abstract. Hidayat RA, Iskandar J, Gunawan B, Partasasmita R. 2020. Impact of green revolution on rice cultivation practices and production system: A case study in Sindang Hamlet, Rancakalong Village, Sumedang District, West Java, Indonesia. Biodiversitas 21: 1258-1265. In the past, farmers of Sindang Hamlet, Rancakalong Village, West Java practiced the wet-rice (sawah) farming system based on the Traditional Ecological Knowledge (TEK) and belief system. They coordinate their planting schedule according to indigenous calendar known as kalender tani or pranata mangsa (Javanese). The various inputs of the sawah farming system, namely rice seeds, organic fertilizers, and pesticides intensively used originate from the village, made little use of farm supplies obtained through purchased from outside (market). In the early 1970s, the Government of the Republic of Indonesia introduced the Green Revolution to increase the rice production of the wet-rice farming system. The five-farming effort (panca usaha tani) programs, namely the use of the High Yielding Rice Varieties (HYVs), the provision for inorganic chemical fertilizers, the use of synthetic pesticides, the development and improvement of irrigation, and the improvement of methods of rice planting methods were intensively implemented. About ten years later, in 1980s, the sawah farmers of Rancakalong Village, Sumedang District, West Java have adopted the Green Revolution program. As a result, the traditional the wet-rice cultivation practices of Rancakalong farmers that was originally based on the low-external inputs has dramatically changed to the high-external-input agriculture, depending more on artificial inputs, such as inorganic fertilizers, pesticides, fossil energy, and modern rice seeds, which originate from outside of the village and generally have to be purchased. The aim of this study is to document and analyze the changing cultivation practices of the wet-rice farming systems, and rice production systems. Study was undertaken in Sindang Hamlet, Rancakalong Village, Sumedang District, West Java. Method applied in this study was a mixed-method, combination of qualitative and quantitative techniques, including observation, semi-structured interviews, and structured interviews applied to 64 respondents. The result of the study showed that the farmers have stopped their traditional cyclical planting schedule based on kalender tani, most local rice varieties have been replaced by the superior or High Yielding Rice Varieties (HYVs), and farmers have become dependent on external inputs, namely inorganic fertilizers, synthetic fertilizers, modern rice seeds, and fossil energy. Consequently, the HYVs have also more vulnerable to diseases and pests, such as brown plant-hopper (Nilarparvata lugens Stal), and also vulnerable to scarcity of water due to drought caused by climate change. This study stresses that a model agriculture system that is ecologically sound, economically viable, and adaptable must be undertaken to develop sustainable agriculture.

Long term effects of management practice intensification on soil microbial community structure and co-occurrence network in a non-timber plantation

Intensive forest plantation management practices, such as use of inorganic chemical fertilizer and herbicides improve productivity, however, their environmental impacts on plantation soil microbial communities and its interaction pattern remain unclear. In this study, we investigated associations between management practice intensities (nutrient-herbicide, nutrient-mowing and manure-mowing), environmental factors including plant coverage, pH, exchangeable calcium (Ca2+), aluminium ion (Al3+), total organic carbon (TOC), C to N ratio (C/N) and soil moisture (SM), and microbial community structure in Chinese hickory (Carya cathayenses) plantations cultivated on two soil types (calcareous and yellow soils). Our results demonstrated that long-term management practices with different intensities significantly changed certain soil environmental factors, and revealed a significant impact on both α and β-diversity of soil bacterial and fungal communities. Specifically, significant higher values of plant coverage, pH, Ca2+, TOC, C/N and SM and lower value of Al3+ were observed under manure-mowing management. Calcareous soil showed significantly higher pH, Ca2+ and TN contents and lower AP values than yellow soil across all three operating intensities. The bacterial community structure was different between the calcareous and yellow soil, but there was no difference for the fungi. Edaphic properties such as pH, Ca2+, TOC and TN were shown to play crucial roles in microbial community structuring, while vegetation-associated factors (vegetation coverage and Al3+) were correlated with fungal community structure. The complexity of microbe co-occurrence network decreased as management practice intensified. The keystone taxa including Bradyrhizobium, Reyranella and Phaselicystis in bacterial network and Rhizophydium and Microascales in fungal network were only observed under manure-mowing, with ecological functions mainly involved in organic carbon degradation and nitrogen fixation. Our results provide insight into the interactions between management practice intensities and soil microbial community characteristics and have implications for the optimization of sustainable forestry management practices and maintenance of microbial diversity and network complexity in over-managed forest plantations.