Agricultural Plants Research Articles

Carbon flow from roots to rhizobacterial networks: Grafting effects

Plants recruit microorganisms from bulk soil by secreting easily available organic carbon into the rhizosphere. Grafting often increases the disease resistance of agricultural plants by modifying this carbon flow from roots into rhizosphere and by recruiting active microorganisms that suppress pathogens. Here, we continuously labeled grafted and ungrafted watermelon plants in a 13CO2 atmosphere to identify the active microorganisms assimilating root exudates. Multi-omics associated technologies (amplicon sequencing, metagenomics and metabolomics) combined with 13C tracing were used to examine the carbon flows, microbial utilization and transformation in the rhizosphere. The number of potentially active bacterial species recruited in the rhizosphere of grafted plants and utilizing root exudates was four times more than in ungrafted plants. These potentially active species matched to metagenome-assembled-genomes (MAGs) mainly belonging to Sphingomonas in the rhizosphere of ungrafted plants, and to Sphingomonas, Chitinophaga, Dyadobacter and Pseudoxanthomonas in the rhizosphere of grafted plants. Sphingomonas possesses the functional potential to metabolize a plant self-toxic substance, namely 4-hydroxybenzoic acid. Furthermore, grafting shaped the complex metabolic interactions and changed the original metabolic dependence between the potentially active bacterial species. Grafting plants diversified belowground carbon flows, activating a greater number of beneficial microbes.

Sweet Archipelagos: Sugar, Empires, and the Making of a Transpacific Insect Trail

Abstract: In 1854, a whaling vessel brought two bundles of sugarcane from Tahiti to Maui, marking the beginning of the Lahaina cane's history and the socioecological transformation of the Hawaiian Islands and the Asia-Pacific. This essay tells a history of sugar through the transpacific crossings of three nonhuman species: sugarcane, the sugarcane beetle borer, and the tachinid fly. It situates nonhuman actors within the historical context of plantation agriculture, capitalist imperialism, and biological globalization of the nineteenth- and twentieth-century Pacific to reconceptualize entomological categories like "pest" and "parasite." Engaging with actor-network theory, animal studies, and island studies, the essay attempts to offer insights into historical agency, human–nonhuman relations, and large-scale ecological change.

The influence of UV-A on some morphometric and biochemical parameters of potato regenerate plants

The ultraviolet radiation (UVR) is the part of light spectrum sunlight and plays a very important role in plant biological processes. The use of ultraviolet irradiation can be a powerful tool for controlling pests and diseases of agricultural plants, as well as a tool for stimulating the synthesis of protective compounds, increasing the nutritional qualities and organoleptic properties of plants. Healthy meristem potato plants after transplantation into soil from in vitro conditions need optimal lighting conditions. In protected soil conditions, the use of additional ultraviolet irradiation of potato plants can significantly increase crop yield. To identify the optimal conditions for using this technique, it is necessary to study the reaction of different potato varieties to ultraviolet radiation. There has been studied the effect of UV-A (wave length is 360 nm, power density is 2.2 W/m2, time period between irradiation is 24 hours) for 10 days after transplanting regenerated plants of five potato varieties into soil. The effects on leaf area, over-ground and root parts, chlorophylls, carotenoid and proline content were investigated. Significant increase in aboveground biomass for ʻLuxʼ and ʻLegendaʼ varieties, root system mass for ʻLuxʼ and ʻAlyaskaʼ varieties, leaf area for ʻLuxʼ variety, proline content in ʻAlyaskaʼ, ʻIrbitskiyʼ, Terra varieties, and reliable decrease of photosynthetic pigments concentrations in the leaves of Legenda potato variety were revealed as affected by UVR. The results obtained correct the knowledge about the effect of UV-A on the growth and development of potato plants.

First Report of Rugonectria rugulosa Causing Dieback of Prunus salicina "Banbianhong" in China.

Banbianhong (Prunus salicina) is a valuable fruit crop cultivated in the southwestern regions of China for its high quality fruit and substantial economic benefits (Wang et al. 2021). In July 2023, dieback disease was observed in Banbianhong in Suijiang County, Zhaotong, Yunnan Province, with an incidence of up to 10%. The disease caused brownish nodules in the cortex of the infected plant, leading to dry cracking, and exposing grayish-brown xylem, which caused the plant to wither and die. Upon longitudinal cutting of twigs, lesions were evident and characterized by browning and necrosis of the cauline bundle and pith within the tissue. The diseased tissues were sectioned into 2 mm2 pieces and surface disinfected with 70% ethanol and 1% NaClO and rinsed with double distilled water. The tissue fragments were plated onto potato dextrose agar (PDA), and incubated for 7 days at 28°C. A total of six isolates were obtained, and two isolates (WG2-1 and WG2-3) were selected for morphological, molecular identification and pathogenicity testing. On PDA, the colony diameter of WG2-1 and WG2-3 were recorded as 5.50±0.56 mm/day and 6.08±0.37 mm/day, respectively. The microconidia of both isolates were zero-septate, smooth, greenish, subglobose to ellipsoidal, and measured 5 to 10 × 1.5 to 3 µm (n = 50) in size. However, macroconidia were not observed. The internal transcribed spacer rDNA (ITS) and β-tubulin 2 (TUB2) genes were amplified using the primer pairs ITS1/4 (White et al. 1989) and Bt2a/2b (Glass and Donaldson 1995). BLAST analysis of the obtained ITS sequences (accession Nos. PP581792) and TUB2 sequences (accession Nos. PP2815212) sequences showed 100% identity with Rugonectria rugulosa (accession nos. MG991753 for ITS and KM232007 for TUB2). Based on these characteristics, the isolates have been identified as R. rugulosa and have been deposited in the Agricultural Environment and Resource Research Institute plant pathogen lab at Yunnan Academy of Agricultural Sciences. In this study, Pathogenicity tests were conducted on one-year-old Prunus salicina "Banbianhong" twigs to complete Koch's postulates. The twigs were wounded using a 1-mm sterile corking borer and 14-day-old mycelium plugs of isolate (WG2-1) were inoculated and covered with sealing films. Sterile PDA plugs were placed into the wounds of control twigs. Eighteen healthy twigs were inoculated with isolates or PDA plugs (n = 6 twigs/treatment, the size of the twigs: 8 cm length and diameter about 0.7 cm, with three replications) and were placed in a closed sterile tray with the wet filter papers in a thermostatic incubator (type, HYC-260) at 28°C, respectively. The twigs inoculated with the isolates exhibited brown lesions site of inoculation, whereas the controls remained asymptomatic. R. rugulosa was successfully reisolated from the lesions but not from these control wounds and was identified by the methods described above. R. rugulosa has been reported to be associated with the die-back disease of Falcataria moluccana in China (Wang et al. 2019). The occurrence and spread of R. rugulosa in growing areas of Prunus salicina "Banbianhong" in Suijiang county have caused severe economic losses. To our knowledge, this is the first report of the die-back disease of Prunus salicina "Banbianhong" caused by R. rugulosa. These results confirm the pathogenicity of R. rugulosa in Prunus salicina "Banbianhong" and provide valuable insights for developing disease management and prevention strategies.

KINETIC, ISOTHERM AND THERMODYNAMIC STUDIES OF THE ADSORPTION OF CRESOL RED DYE USING AGRICULTURAL WASTES

Agricultural wastes and plant biomass are alternative low-cost adsorbents because they can be used without or with a minimum processing. In the present study, batch experiments were carried out to study the adsorption of cresol red (CR) unto mango leaf (ML) and orange peel (OP). Several parameters that affect adsorption process such as pH, adsorbent dosage, contact time, initial dye concentration and temperature were investigated. FTIR and SEM were used to determine the functional group responsible for adsorption. The results revealed that the highest adsorption efficiency was at pH 5 for the two adsorbents. It was also discovered that CR removal efficiency increased with the increase in contact time and adsorbent dosage while adsorption capacity was higher with increase in initial dye concentration but removal efficiency was lowered. The kinetics conform with the pseudofirst-order kinetic model for mango leaf but conform with the pseudo-second-order kinetic for orange mesocarp due to the value of the correlation coefficient (R2). Based on the value of correlation coefficient, the experimental results for the removal by mango leaf best fitted the Langmuir isotherm model with monolayer adsorption capacity of 70.64 mg. g-1, while Freundlich isotherm model was best fitted to the experimental results for the adsorption of CR by Orange peel. The thermodynamic results revealed that the process is spontaneous and endothermic.

Sustainable insulation panel for buildings made of rice husks and posidonia

The design of the building envelope is crucial to achieve adequate thermal comfort by means of insulating materials that prevent heat flow without excessive energy costs. Generally, materials based on fossil fuel content a large carbon footprint, so when environmental criteria are becoming increasingly important, it is necessary to search for more sustainable insulation materials with a low environmental impact, lower energy use or few CO2 emissions. The aim of this work is focussed on using the agricultural residue or plant debris that sea expels, specifically rice husk and posidonia oceanic leaves. The properties of both materials are studied by experimental tests at different densities to define appropriate thermal conductivity. In addition, acoustic performance, sensitivity to water, durability (mould fungus), mechanical properties and fire reaction are tested to evaluate their behaviour in comparison to other commercial insulation materials. The results highlight the proper performance of rice husks and posidonia as material for insulation panels with 0.055 and 0.045 W/mK of thermal conductivity, respectively. Furthermore, rice husks and posidonia offer a promising reaction to fire with low heat release and smoke production for an element that has been critical in buildings in past catastrophic fires.

Ibn Wāfid Andalusi, a medieval physician, pharmacist, and botanist, with a look at his most important work Al-Adwiyah Al-Mufradah.

The mastery of medical sciences, pharmacy, and botany can be seen in the records of Andalusian scientists. This descriptive-analytical research introduces one of the scientists of the 10th and 11th centuries AD. Medical knowledge and its affiliates are taken from the medical heritage of ancient civilizations. Andalusian scientists changed Andalusia's agricultural and economic situation by adopting new agricultural methods, especially irrigation and planting of medicinal plants. The name of Ibn Wāfid shines among Andalusian scholars. He was one of the theorists in the field of pharmacology in the Middle Ages. His practical method of treating patients is remarkable. His therapies tend to use nutritional methods more than prescribing drugs. He preferred single medications to compound ones. He insisted on curing diseases through hydrotherapy in mineral springs. While working in botany, Ibn Wāfid also specialized in medicine and pharmacy. He also benefits from the experiences of his master Zahrāwi while using the works of Galen, Aristotle, and Dioscorides. One of his honours was the establishment of several botanical gardens for the kings of the time. Ibn Wāfid's attempt at the flourishing of pharmacology, botany, and medicine can be considered a significant contribution to the visibility of these sciences in Medieval Andalusia.

Forgotten project of a private agricultural plantation in the Khanate of Khiva, Uzbekistan

ABSTRACT This article re-evaluates a failed large irrigation enterprise and agricultural plantation in the Khanate of Khiva, an Imperial Russian protectorate in contemporary Uzbekistan, during the 1910s. Co-initiated by Russian entrepreneurs and the Khivan government, this project has been considered one of several lucrative, speculative ventures by Russian capitalists exploiting imperial privileges. This article demonstrates that the entrepreneurs involved in the dacha Lawzan enterprise possessed adequate capital and technology for this large-scale project. However, the project was hampered by legal restrictions put in place by the imperial government and by lingering conflict with nomads in the Khanate and ultimately failed. The case of dacha Lawzan exemplifies government–entrepreneur tension in the colonial territories of Imperial Russia, which impeded the economic development projects initiated by local governments to attract private capital to irrigation and cotton cultivation.

Growth of complete ammonia oxidizers on guanidine

Guanidine is a chemically stable nitrogen compound that is excreted in human urine and is widely used in manufacturing of plastics, as a flame retardant and as a component of propellants, and is well known as a protein denaturant in biochemistry1–3. Guanidine occurs widely in nature and is used by several microorganisms as a nitrogen source, but microorganisms growing on guanidine as the only substrate have not yet been identified. Here we show that the complete ammonia oxidizer (comammox) Nitrospira inopinata and probably most other comammox microorganisms can grow on guanidine as the sole source of energy, reductant and nitrogen. Proteomics, enzyme kinetics and the crystal structure of a N. inopinata guanidinase homologue demonstrated that it is a bona fide guanidinase. Incubation experiments with comammox-containing agricultural soil and wastewater treatment plant microbiomes suggested that guanidine serves as substrate for nitrification in the environment. The identification of guanidine as a growth substrate for comammox shows an unexpected niche of these globally important nitrifiers and offers opportunities for their isolation.

Analysis of Maize Planting Mode and Simulation and Optimization of Ridging and Fertilization Components in Arid Area of Northwest China

The arid area of Northwest China belongs to the rain-fed agricultural area of the Loess Plateau, and water resources have become one of the important factors limiting agricultural development in this area. This study employed the AquaCrop model to predict the yield advantages and environmental adaptability of maize in Dingxi City from 2016 to 2020 under two cultivation practices: ridge tillage (100% film coverage with double ridge-furrow planting) and flat planting (81.8% film coverage with wide-film planting). The numerical simulation of the tillage and fertilization process of the double-ridge seedbed was carried out by EDEM, and the key components were tested by the Box–Behnken center combination test design principle to obtain the optimal parameter combination. The results showed that ridge planting was more suitable for agricultural planting in rain-fed arid areas in Northwest China. The simulation analysis of ridging and fertilization showed that the forward speed of the combined machine was 0.50 m/s, the rotation speed of the trough wheel of the fertilizer discharger was 39 rmp, and the rotary tillage depth was 150 mm. The qualified rate of seedbed tillage was 93.6%, and the qualified rate of fertilization was 92.1%. The research shows that the whole-film double ridge-furrow sowing technology of maize is more suitable for the rain-fed agricultural area in the arid area of Northwest China. The simulation results of the ridging fertilization device are consistent with the field experiment results. The research results provide a certain technical reference for the optimization of the whole-film double ridge-furrow sowing technology.

The sensitivity of agricultural biogas plants to changes in energy prices in Poland

In Poland, despite ambitious plans from 15 years ago, when it was assumed that by 2020, an agricultural biogas plant would be standard in every commune, the potential of agricultural biogas has not been used due to the lack of stable legal regulations and financing programmes for the construction of the plants. The situation has now changed due to new forms of support systems, which motivated the authors to compare two agricultural biogas plants operating in the certificate system and the support system in the form of feed-in premiums. Moreover, the authors pointed to differences in the number of agricultural biogas plants and their capacity by voivodeship due to changes in legal conditions in force in two periods: from 1 January 2011, to 30 June 2016, and from 1 July 2016, to 19 January 2024. Based on the research methods used ‒ including Earnings Before Interest, Taxes Depreciation and Amortisation, the Internal Rate of Return, risk matrix and data analysis in spatial terms ‒ it was indicated that: 1. agricultural biogas plants are characterised by very high sensitivity related to the probability of risk in the case of investment costs, substrate prices and changes in energy prices; 2. financial support is important at the stage of construction of a biogas plant, which largely makes it possible to shorten the payback period and thus increase the willingness of future investors to invest in biogas plants and 3. in the periods analysed, significant differences were noted in the spatial location of biogas plants due to trends towards lower-power biogas plants, which is probably dictated by the constant and predictable premium system in the new support system.

First report of anthracnose caused by Colletotrichum fructicola on winter jasmine (Jasminum nudiflorum) in China.

Winter jasmine (Jasminum nudiflorum Lindl.) is a medium-sized, deciduous shrub native to China that has become a popular choice among gardeners and landscapers. In 2020 to 2021, symptoms of anthracnose including brown necrotic spots, enlarged irregular lesions and leaf blight were observed on leaves of 20 winter jasmine shrubs in a public garden (22°34'58'' N; 113°56'23'' E) in Shenzhen, China, and with an estimated disease incidence of 65%. Tissues samples (6 × 6 mm2) surrounding the necrotic spots were surface sterilized with 75% ethanol for 30 s, followed by 2% NaClO for 1 min, then rinsed with sterile water for three times and dried with sterile filter paper. Tissues were placed on potato dextrose agar (PDA) medium and incubated at 25℃. After 3 to 7 d, pure cultures were obtained by transferring hyphal tips to new plates and 32 isolates producing Colletotrichum-like colonies were obtained from 40 tissues (isolation frequency=32/(4×10)=80%). Three representative isolates YCH09, YCH23 and YCH32 were selected for further study. Three selected isolates were identical in morphological characteristics. Colonies on PDA after 5 d at 25℃ were white to gray with cottony mycelia and grayish-white on the underside of the culture. Conidia (n = 60) measured 15.4 ± 1.1 µm (13.0 to 17.1 µm) in length and 5.4 ± 0.3 µm (4.9 to 6.0 µm) in width and were hyaline, single-celled, cylindrical with rounded ends. Appressoria (n = 15) measured 7.1 ± 0.1 µm (5.3 to 8.9 µm) in length and 5.2 ± 0.2 µm (4.1 to 6.2 µm) in width and were brown to dark brown, ovoid. These morphological features were aligned with those of Colletotrichum spp. (Weir et al. 2012). Sequences of five genetic markers of representative isolates YCH09, YCH23 and YCH32 including the rDNA internal transcribed spacer region, chitin synthase, partial actin, β-tubulin 2 and Apn2-Mat1-2 intergenic spacer and partial mating type (Mat1-2) region were 99.3 to 100% identical to the ex-type isolate of C. fructicola strain ICMP 18581 (Zhang et al., 2020). From the maximum likelihood phylogenetic tree which was constructed based on concatenated sequences, three representative isolates (YCH09, YCH23 and YCH32) were clustered with other isolates of C. fructicola. The above morphological and molecular characteristics suggest that causal agent was C. fructicola. Pathogenicity was tested using a whole-plant assay. Five healthy plants were inoculated by spraying a conidial suspension (1.5×104 conidia/ml; 20 ml per plant) of the isolate YCH23 onto the foliage (Marshall et al., 2023). Three noninoculated control plants were sprayed with sterile water. All plants were placed in a greenhouse at 25±2℃ with approximately 75% relative humidity. Yellow lesions appeared on leaves of inoculated plants as early as 4 days after inoculation (DAI), and irregularly shaped brown spots similar to those observed in the field were formed on 10 DAI. Noninoculated plants remained asymptomatic. Colletotrichum isolates resembling morphological characters of YCH23 were reisolated from all inoculated plants, then identified as C. fructicola by DNA sequence analysis. C. fructicola is a well-known fungus causing anthracnose on more than 63 plant species including agricultural and horticultural plants worldwide (Talhinhas and Baroncelli, 2021). To our knowledge, this is the first report of C. fructicola infecting J. nudiflorum plants in China. Since its potential risk to other horticultural plant species, precautions may be necessary to minimize the spread of this fungi.

Effect of Burned Multi-Crop Ashes on Faba Bean-Development Parameters.

The use of burned plant biomass ashes could help not only with respect to utilizing combustion residues, but also with respect to optimizing the nutrition of cultivated agricultural plants without harming the environment. With this aim, a pot experiment of the effects of multi-crop biomass ash on faba bean seedlings was carried out in the Academy of Agriculture of the Vytautas Magnus University (VMU). Four ash fertilization rates were tested: 1. unfertilized (N0, comparative-control treatment); 2. fertilized at a low rate (N1, 200 kg ha-1); 3. fertilized at an average rate (N2, 1000 kg ha-1); 4. fertilized at a high rate (N3, 2000 kg ha-1). Final observations showed that ash fertilization significantly increases the height of faba bean sprouts by 21-38%, the length of the roots by 10-20% and the chlorophyll concentration in the leaves by 17%. The average green biomass of faba bean sprouts consistently increased with increasing fertilization rate, from 56% to 209%. Dried biomass increased by 160-220%. With increasing ash fertilization rate, the percentage of dry matter in the roots decreased by 10-50%. We recommend fertilizing faba bean with medium (1000 kg ha-1) and high (2000 kg ha-1) ash rates, as these rates led to the largest plants with the highest productivity potential.

THE EFFECT OF TILLAGE TECHNOLOGY ON THE AMOUNT OF WEEDS AND THE YIELD OF POTATOES

Weeds deprive agricultural plants of life factors and deteriorate their productivity and quality indicators. Therefore, agricultural experts try to reduce the amount of weeds to minimize the damage caused by it. First of all, it is important to know their biological characteristics, extent of spread, species composition, which is reflected in the article, in order to carry out the measures against weeds correctly. It is known from the species composition of weeds spread in potato crops that it is possible to eliminate the damage caused by applying the correct soil cultivation technology. In the research work, when the intermediate plant (field pea + oat mixture) planted under rotation conditions is disked and mixed with the soil and plowed as a result of soil cultivation measures, the reduction of the amount of weeds significantly increases the productivity. Here, the yield increase was 58.5 q/ha or 37.55% compared to the variant that was left fallow after wheat, plowed 25-30 cm and sprayed with herbicide. This suggests that it is possible to significantly increase productivity while minimizing the use of herbicides by applying the correct tillage technology in potato crops.

Ancestral lineages of dietary exposure to an endocrine disrupting chemical drive distinct forms of transgenerational subfertility in an insect model

Across the globe, many species of insects are facing population decline. This is largely driven by anthropogenic changes to the environment, including the widespread exposure of invertebrates to endocrine disrupting chemicals (EDCs), which impair fertility. To test whether generations of Drosophila melanogaster born from parents exposed to a common dietary EDC, equol, could recover reproductive function, we quantified the reproductive capacity of the two subsequent generations. Using a novel suite of flow cytometry assays to assess sperm functionality in real time, we find that sperm function is compromised across three generations, even after non-exposed in individuals contribute to the breeding population. Though the sex ratio alters in response to EDC exposure, favouring the survival of female offspring, most lineages with ancestral EDC exposure exhibit persistent subfertility in both the male and female. Male offspring with ancestral EDC exposure present with reduced fertility and dysfunctional spermatozoa, whereby spermatozoa are metabolically stressed, lack DNA integrity and present with permanent epigenetic alterations. Across generations, male and female offspring demonstrate distinct patterns of reproductive characteristics, depending upon the specific lineage of EDC exposure. Our results illustrate how dietary EDCs present in agricultural plants could promote transgenerational subfertility and contribute to declining insect populations.

Efficient nutrient and antibiotics removal from aquaculture wastewater using different microalgae-based systems by agricultural multi-phytohormone induction

The present study innovatively explores the impact of adding agricultural mixed plant hormones (gibberellin acid-indole-3-acetic acid-brassinolide, GIB) on simultaneously removing nutrients and antibiotics out of aquaculture wastewater within different four microalgae-bacteria-fungus symbionts. The results indicated that under the optimal symbiotic technology (Chlorella vulgaris+S395-2+Clonostachys rosea) and the best hormone GIB (20 mg L−1) addition, both growth characteristics and photosynthetic performance of microalgae-bacteria-fungus symbionts were optimal. Under optimal treatment conditions, the average nutrient removal efficiency (TN and TP) reached 93.71 ± 5.02 % and 93.56 ± 4.07 %, separately, whereas the average removal efficiency of antibiotics (oxytetracycline, ciprofloxacin and sulfadiazine) were 99.46 ± 0.17 %, 89.53 ± 5.41 %, and 85.68 ± 6.82 %, respectively. This study offers a promising new direction for algal treatment technology, particularly in the concurrent removal of antibiotics and nutrients.

From A Supervisor To A Plantation Owner

The looming financial crisis threatened to transform Mr. Rostam's thriving agribusiness into a sinking ship, casting a shadow of uncertainty over his entrepreneurial dreams. The once-promising future now appeared murky and fraught with challenges, leaving him to navigate the business desperately to keep his venture afloat. It is a test of resilience, innovation, and unwavering determination as he grapples with the harsh realities of an uncertain market. With limited resources, he coped with more of the challenges of a struggling business. The road ahead seemed daunting, with uncertainty lurking at every turn. Mr. Rostam pondered over the situation, feeling the weight of responsibility on his shoulders; he muttered, "The business has reached the critical point, and failure was not an option”. Mr. Rostam has to look for the right opportunity and decide about taking the next big leap of faith to start his next agriculture business venture. Terengganu Agrotech Development Corporation Sdn. Bhd. (TADC) looking for proposals to develop a large palm oil plantation farm in Terengganu state. Mr. Rostam has to develop the right plan with a partner that can invest in the proposed corporate farming project.

Productivity and Yield of Patchouli (Pogostemon cablin Benth) in Community Forest using Agroforestry Patterns in Tommo District, Mamuju Regency, West Sulawesi Province

Abstract The productivity of patchouli plants in Indonesia still needs to improve. This is because patchouli cultivation is generally carried out using a monoculture and shifting cropping pattern, which causes land degradation. This study aims to determine the productivity and yield of patchouli (Pogostemon cablin Benth) in community forest using agroforestry patterns in Tommo District, Mamuju Regency, West Sulawesi Province. The study used observation, survey, interview, and questionnaire methods. Respondents were selected using a purposive sampling method of 30 respondents who cultivated patchouli plants using an agroforestry system in community forests. In-depth interviews were conducted with these respondents, followed by a survey of their patchouli cultivation area. The findings revealed that the average annual production of patchouli plants in community forests employing an agroforestry approach amounted to 8,604 kg/year through two harvests on an average land area of 0.74 hectares. Consequently, the average patchouli plant productivity is 10,697.26 kg/ha per year. Patchouli production consists of leaves and twigs that the community has dried and then distilled using conventional distillation equipment. The average yield from the distillation of patchouli leaves and twigs into patchouli oil is 1.96%. Consequently, the productivity of patchouli oil that can be obtained from cultivating patchouli plants is around 209.67 kg/ha per year, equivalent to 246.67 litres/ha per year. The productivity and yield of patchouli plants in the agroforestry pattern are generally lower than in the monoculture pattern, with an average productivity of 13,279 kg/ha per year and a yield of 2.83%. Still, the agroforestry pattern provides added value by producing forestry and agricultural plants combined with the patchouli plant.

Analysis Of Mangrove Land Cover In The Sawo Marine Conservation Area, North Nias District

Sawo sub-district of North Nias Regency has a mangrove ecosystem that has been designated as a Regional Marine Conservation Area (KKLD) with an area of 29,230.85 ha. The 2005 earthquake and tsunami are reported to have caused damage to mangrove ecosystems due to rising land levels. The increase in land surface has resulted in the destruction of mangroves in this area. This has an impact on the sustainability of the mangrove ecosystem in this region and is important to study. The purpose of this study is to analyze changes in mangrove land cover after the tsunami in 2006 to 2022 and to analyze the impact of changes in mangrove land cover. The results found that mangrove land cover continues to experience a reduction in area, in 2006 an area of 139.78 ha and continues to decline until the remaining 70.87 ha in 2022. This is due to the increasing population growth that causes mangrove forest degradation and land conversion into agricultural land, plantations and infrastructure. The increase in population is a driving force, land clearing for settlements and plantations is a pressure factor (Pressures), land use change is a factor of existing conditions (State), reduced mangrove land area is part of the impact (Impact) and coastal spatial planning, counseling to reforestation is a response (Response). Land conversion to other uses is a contributing factor to the continued loss of mangrove land in this area.Keywords: Mangrove, Land cover, GIS, DPSIR

The Economic Efficiencies of Investment in Biogas Plants—A Case Study of a Biogas Plant Using Waste from a Dairy Farm in Poland

High investments and low economic efficiency of agricultural biogas plants operating on farms are two of the main barriers to the development of the biogas plant sector. Identification of economic and financial problems related to the operation of such facilities allows for the reduction of entry barriers for private investors, especially farmers. The aim of this research was to analyze the economic efficiency of investing in an agricultural biogas plant operating at a dairy farm. For the analysis, the case study method was applied. The economic efficiency of investment in a biogas plant was assessed using six different cash flow options. The NPV (net present value) and IRR (internal rate of return) methods were applied to assess the economic efficiency of the investment. It was found that the investment project for an agricultural biogas plant with a capacity of 0.499 MW located at a dairy farm required a subsidy of approximately 40–60% of the value of to ensure satisfactory economic efficiency. It has been shown that a particularly important aspect in assessing the economic efficiency of an investment in an agricultural biogas plant is the use of an economic calculation that takes into account the valuation and quantification of all positive external effects of such projects.