Farming Subsystem Research Articles

Keragaan Agribisnis Usaha Jamur Tiram Putih di Kelurahan Anduonohu Kecamatan Poasia Kota Kendari (Studi Kasus di Usaha Tiga Putra Farm)

Oyster mushroom is a type of wood mushroom that Indonesia commonly consumes. It has a fruiting body that grows in bloom to form a shallow funnel shell (oyster). This study aimed to determine the agribusiness performance of the White Oyster Mushroom (Pleurotus ostreatus) in Anduonohu ​​Village, Poasia District, Kendari City. Case study on Tiga Putra Farm Business. This research was conducted in September 2021. The object of this research was the Tiga Putra Fram Timber Mushroom business. The method used in this study is Qualitative Descriptive Analysis. The type of data in this study used primary data, namely direct interviews, and secondary data, namely library literature. The variables used in this study are 1. The informant's identity includes age, education level, business experience, and some family dependents, 2. Agribusiness performance from this study is in the form of support in the agribusiness subsystem, which includes production facilities (seeds, fertilizers, tools /machinery, and mushroom house), cultivation and farming subsystem (planting, maintenance, processing), and marketing subsystem (distribution). The results of this study are the agribusiness performance of the white oyster mushroom (Pleurotus ostreatus), namely the procurement and provision of production facilities, including the procurement of mushroom houses, seeds, tools, and machines. Cultivation and farming include oyster mushroom production, maintenance, and harvest. Oyster mushroom product marketing is done online and offline by online method, namely posting oyster mushroom products on several social media platforms such as Facebook, WhatsApp, and Instagram. Thus the range of product marketing can be more comprehensive. Offline marketing to resellers of oyster mushrooms that will be resold, such as the Ummushabri Kendari and Hypermart.

Analysis Of Beef Cattle Agribusiness In Deli Serdang Regency

This study aims to analyze the effect of each agribusiness subsystem on the income of beef cattle breeders in Deli Serdang Regency. The research was conducted in 3 (three) sub-districts in Deli Serdang, Hamparan Perak, Sinembah Tanjung Muda Hilir and Kutalimbaru Regencies using a simple random sample selection method. The total sample in this study were 75 breeders. Data were analyzed by scoring and path analysis. The results of the path analysis show that the agribusiness subsystem that has the most influence on the income of beef cattle breeders is the livestock farming subsystem of 0.466. The direct effect of the livestock farming subsystem on income is greater than the entire agribusiness subsystem studied. If the farmer wants to increase the income of beef cattle, then an increase is made in the livestock farming subsystem. The influence of the agribusiness subsystem on the income of beef cattle farmers through the marketing subsystem shows no effect. The influence of the agribusiness subsystem on the income of beef cattle breeders through the supporting subsystem shows that there is an influence on the income of beef cattle breeders, namely in the livestock farming subsystem of 0.821.

Analysis and Suppression of High-Frequency Resonance for Offshore Wind Power Grid-Connected Converter Considering Cable Capacitance Effect

Large-scale offshore wind farms have become the development trend in wind power generation. Long submarine cables are used to collect electrical energy in the collection networks of offshore wind farms. However, the distributed capacitance of cables cannot be ignored, which makes the impedance of the collection network complex and changeable. It is common to encounter high-frequency harmonic resonance (HFHR) problems when cables interact with wind turbine generators (WTGs). The HFHR may threaten the safe and stable operation of wind turbines. In order to solve this problem, firstly, the impedance of a collection network was constructed. Furthermore, the wind farm collection network was divided into the equivalent wind turbine subsystem (EWTS) and the remaining equivalent wind farm subsystem (REWFS). Then, the mechanism of HFHR was revealed based on the impedance stability analysis method. The effects of cable parameters, the number of connected WTG, and the grid impedance on the HFHR of the interconnected system were also analyzed. Finally, the hybrid damping control method, combining active damping control (ADC) and passive damping control (PDC), was proposed to suppress the resonance. A simulation and experiment were performed to verify the effectiveness of the analysis results and proposed control method.

Performance of environmentally sound cassava farming as an effort to increase income after covid 19 in the Bengawan Solo Wonogiri Watershed

The limited sources of income in the Wonogiri Regency will impact the tendency of repressive community actions towards empowering surrounding resources, including cassava farmers. After Covid 19, the cassava economy was used as leverage for changes in the rural economy. The objectives of this study are (1) to determine the influence of environmental management on the inputs and outputs of cassava farming, (2) to diagnose fluctuations in the vulnerability of cassava farming, and (3) to analyze cassava problems in production and farming sub-systems. The research locations were in 2 subwatershed of Bengawan Solo areas, namely the Keduang Sub-Watershed (Ngadirojo District and Jatiroto District) and the Wiroko Sub-Watershed (Tirtomoyo District), with 120 respondents. The analysis used is the input-output analysis of farming, descriptive analysis, and t-test analysis. The results showed a difference between an environmentally sound cassava farming business and one that does not, with an error rate of 1% and a coefficient of 1,802% in terms of income (output) and cost (input). The vulnerability occurs when cassava cultivation is processed on a sharp slope of the soil, making it highly costly. The performance of environmentally sound cassava farming positively impacts production and income, but there are limited funds and technology.

STRATEGI PENGEMBANGAN AGRIBISNIS KELAPA DALAM (Cocos nucifera L.) SEBAGAI KOMODITAS UNGGULAN DI KABUPATEN BUTON UTARA

This study aims to analyze the coconut commodity as a leading commodity in North Buton Regency and to analyze the income of coconut farming in North Buton Regency. This research was conducted in North Buton Regency for three months, from July to October 2020. The type of data used is quantitative data derived from primary data and secondary data. Data collection is done by way of interviews, observation, and documentation. The sample in this study consisted of 60 coconut farmers and 10 informants who were determined purposively (purposive sampling). Data analysis used is qualitative descriptive analysis, LQ analysis and income analysis. The results of the study show that coconut in North Buton Regency is a superior commodity because based on the production approach the average LQ value for five years (2014-2019) is greater than one (> 1) which is 3.057. The deep coconut agribusiness subsystem in North Buton Regency includes; 1) sub-systems of production facilities such as coconut seeds, coconut peelers, fruit pulp tools, machetes, tarpaulins, sprayers, and lawn mowers; 2) farming subsystem includes planting techniques, land clearing, and harvesting; 3) processing subsystem includes production of copra and coconut shell charcoal; 4) marketing subsystem and 5) supporting advice subsystem. The average income of deep coconut farming in North Buton Regency is Rp. 16,479,910.02. The priority programs for the development of deep coconut agribusiness strategies in North Buton Regency are: 1) Improving the quality of human resources for farmers with a QSPM value of 12.38. 2) Maximizing coconut derivative products with a QSPM value of 12.01. 3) Managing deep coconut agribusiness by utilizing appropriate technology with a QSPM value of 11.96 4) Using superior variety seeds with a QSPM value of 11.86

Arabica Coffee Agribusiness in Prigen District, Pasuruan Regency.

Arabica coffee is an exotic commodity whose demand continues to grow every year. Agribusiness is an important aspect of the development of Arabica coffee commodities, agribusiness consists of four subsystems namely production facilities subsystem, on-farm subsystem, processing subsystem, and marketing subsystem. This study aims to analyze the effect of each subsystem on the income of Arabica coffee agribusiness and the influence between agribusiness subsystems on Arabica coffee agribusiness. This study used the PLS-SEM method with Warp-PLS software. The test results show that there is a positive and significant influence between the production facilities and infrastructure subsystem variables on the Arabica coffee agribusiness income, the marketing subsystem variable to the Arabica coffee agribusiness income variable, the production facilities and infrastructure subsystem variable, the influence of the farming subsystem variable on the processing subsystem variable, the processing subsystem variable on the marketing subsystem variable. Then it is known that there is a positive influence and no significant effect or a weak level of significance between the farming subsystem variables on the Arabica coffee agribusiness income variable, and there is a negative influence and there is a significant influence between the processing subsystem variables on the income variable of Arabica coffee agribusiness.

ANALISIS PENDAPATAN DAN PEMASARAN USAHATANI KOPI DI KECAMATAN WAY RATAI KABUPATEN PESAWARAN

This study aims to analyze income of arabika and robusta coffee farming, and the marketing channel patern. This research was taken in Harapan Jaya and Pesawaran Indah Villages, Way Ratai District, Pesawaran Regency. The sample of this study consisted of 30 robusta farmers and 13 arabica coffee farmers. The farming subsystem was analyzed descriptive quantitatively to analyze the farmer's income in the last year and to assess the feasibility of farming. The marketing channel pattern was analyzed descriptive qualitatively to determine the pattern of marketing channels of arabica and robusta coffee. The results showed arabica and robusta coffee farming in Way Ratai District is profitable. Eight percent of arabica coffee farmers used marketing channel II as the most efficient marketing channel, and 40 % of robusta coffee farmers used channel II as the most efficient marketing channel because it has the shortest marketing chain. Keywords: arabica, coffee, channel, income, marketing, robusta.

KAJIAN SISTEM AGRIBISNIS SAYURAN HIDROPONIK DALAM MENUNJANG KETAHANAN PANGAN DI KOTA TARAKAN

Food security will remain a fundamental problem in meeting the basic needs of the community, not only in rural areas but also in urban areas. Tarakan City is a city located in North Kalimantan and has a population density that causes limited availability of land for agriculture. One solution to overcome this is hydroponic cultivation to support food self-sufficiency in border areas. This study aims to identify and examine through an agribusiness system approach including input subsystems, farming/cultivation, processing, marketing and hydroponic business support services. The research method used is descriptive qualitative through agribusiness systems approach. The method of determining the sample is purposive sampling. The results of this study indicate that hydroponic vegetable farming in Tarakan City that the upstream subsystem includes production facilities and infrastructure such as screenhouses, seeds, nutrition, and agricultural machinery. On Farm subsystem covers an area of 10 x 15 m2 with a total income of Rp.1,373,000, per production. The downstream subsystem includes processing products such as sorting and packing and using a marketing mix approach consisting of two marketing channels. The supporting subsystem consists of government institutions, namely the Food and Agriculture Service, the Industry, Trade and SMEs Service, as well as a private institution, namely PT. Medco. Key words:, Agribusiness, Food Security, Hydroponics

Material flow analysis of the nitrogen loading to surface water of Miyun reservoir watershed under uncertainty

Nitrogen (N) was one of the primary causes to water environment depravation, having a thorough understanding of N loading to water body is important for reducing the N pollution purposefully. In this research, we took the Miyun reservoir watershed as a typical area, of which a material flow model of the N metabolism was built. Afterwards, the material flow analysis (MFA) was conducted to identify the main pathways that generated N loading. And then the Monte Carlo (MC) method was applied to make uncertainty analysis of the N loading calculated through the MFA. The MFA results showed that the total N loading to surface water of the Miyun reservoir watershed was 5505.42 × 103 kg N, of which about 74.89% was originated from the agriculture subsystem (i.e., crop planting, fruit planting and vegetable planting subsystems). The main pathways of the agriculture subsystem that generated N loading were recognized as maize, chestnut, apple, pear, cabbage, cucumber and tomato planting. The uncertainty analysis results revealed that the N loading calculated from the MFA had some uncertainty, of which the fruit planting and industry subsystem had the biggest uncertainty, while the N loading from the fish farming subsystem had the lowest uncertainty. To make directed actions to protect the water quality of the Miyun reservoir watershed, the main pathways of each subsystem that generated N loading need to be regulated. This study provided a new framework of combing the MFA and MC method to simulate N loading to surface water at watershed scale, and was of vital significance to provide decision support for the watershed N pollution management globally.

Internal flow of nutrients in organic farming systems in tidal swamp

Sustainable nutrient management is critical to the success of an agroecosystem. The potential of nutrient flow to agroecosystems in tidal swamps can be observed in several of soil and water management. Tidal swamp land management based on surjan and tabukan system are often used to farm several sub-agricultures, namely rice fields, ponds, and citrus plantations. This study aimed to determine N nutrients’ input, output, and internal flow in organic farming systems. This study is limited to observing the internal components. The integrated organic farming system in tidal swampland, usually used for orange in the raised beds and rice in the sunken beds/wetland sections or fishponds, demontrated the potential for inorganic N-flow between farming sub-systems and between components within the system. Scenarios for the use of rice straw for external production sub-systems such as for citrus plantations and composting for external purposes need consideration. This potential can be a sub-component of nutrient input for other sub-systems or the next planting season. The simulation of the integrated rice-citrus-fishpond agroecosystem model showed a positive nutrient balance, especially N nutrients. This model needs to be further developed.

Ina

The approach of sustainable natural resource processing is increasing with the awarening development of global communities and the keys to socio-economic improvement. Bamboo is the types of plants that can be used to fulfill the resource needs and as another alternative to improving the economy engagement in rural creative industries. Bamboo is a well-known plant, especially for rural communities. Ngada is a center development of bamboo in Indonesia, it is because of the abundant potential of bamboo. The utilization of bamboo for the society in Ngada has become as a part of life and has been inherited by their ancestors and can be a focus for economic community development and as promising source of income. The use of bamboo by the society of Ngada in general as a source of household needs so that is an indicator that bamboo is worth more than just a plant. There are further utilization of bamboo that can be divided into: 1) The utilization of upstream subsystem; 2) The utilization of on farm subsystem; 3) The utilization of downstream subsystem, with many utilization areas of bamboo, allows this to be first stage to determining the policy in Ngada that focused on developing of bamboo.

SISTEM AGRIBISNIS INTEGRASI PADI KERBAU DAN POLA PEMELIHARAAN KERBAU DI KECAMATAN PAMPANGAN SUMATERA SELATAN

<p><em>Th</em><em>is study aimed </em><em>to determine and analyze the integrated rice-buffalo agribusiness system and to describe the pattern of buffalo raising in Pampangan District. This research was conducted in Pampangan District in July 2020. This research is a survey that took 30 samples purposively. Primary and secondary data obtained from the field survey were tabulated and analyzed descriptively-qualitatively. The integrated rice-buffalo agribusiness system in Pampangan District consists of the upstream subsystem, namely the provision of production facilities for rice-buffalo integration activities, the farming subsystem in the form of rice cultivation and livestock raising, the downstream subsystem, namely post-harvest and management of rice-buffalo waste used for organic fertilizer and silage. The supporting subsystem is that farmers have joined G</em><em>apoktan</em><em> and have received training from BPTP on making compost. </em><em>R</em><em>aising buffalo in Pampangan District is still traditional, which is almost entirely relying on nature. The buffaloes are released in the morning and put back in the afternoon, allowed to eat the feed in the grazing environment</em><em>. In contrast, </em><em>for the health of the buffalo, it is still done as necessary and not as intensive</em><em>.</em><em> The profit-sharing system between the owner and the custodian is known as the half system. The results of buffalo livestock production are obtained from the sale of buffalo and from the processing of buffalo milk production into sugar, sagon, curd or cow oil</em><em> (a popular local term in Pampangan Sub-district)</em><em>.</em></p>

Marketable dan Merketed Surplus Beras di Kabupaten Banyumas

Efforts to increase rice production must be integrated from the upstream sub-system, the farming sub-system, the downstream sub-system and the support sub-system. Upstream sub-system development is very important and cannot be ignored. Ownership of land by farmers is very small with an area of less than 0.5 hectares, most farmers are actually only landless farm laborers who depend on their work as agricultural laborers. Rice farmers in Banyumas Regency cannot be clearly defined as a producer when looking at the consumption side of the farmer. This study aims to determine the performance of rice farming, determine the magnitude of marketable surpluses and marketed surpluses of rice and analyze the factors that influence the marketed surpluses of rice in Banyumas Regency. Data analysis uses marketable analysis and marketed rice surplus, multiple linear analysis. The results showed an average area of land owned by 0.21 ha, with a productivity of 4,823.69 kg / Ha (GKP), 4,149.34 kg / Ha (GKG), 2,603.30 kg / Ha (Rice). The marketable value of rice surplus is 22,624.20 kg / MT or 85.67 percent of the total product and the marketed value of rice surplus is 13,422.83 kg / MT or 59.33 percent of the marketable surplus value. Product allocation is more used to pay for harvest labor and family food consumption. The results of multiple linear regression analysis with the model obtained Y = -146.89 + 0.87X1-1.94X2 + 4.94X3 + 1X4-83.80X5-0.009X6 + 2.95X7-7.23X8-1.6X9 + 34 , 3X10-0.007X11 + e. Marketed rice surpluses in Banyumas Regency are influenced by the variable amount of products and farming costs in nature.

Life cycle environmental impact assessment of rice-crayfish integrated system: A case study

Rice-crayfish integrated system (RCIS) as a sustainable agricultural system has been widely and rapidly promoted in China. However, the environmental impact potential of RCIS is still unknown compared with conventional rice monoculture system (RM). A life cycle assessment (LCA) methodology was applied to characterize the environmental performance and potential improvement opportunities related to RM and RCIS, and a questionnaire survey of 300 farmers was carried out in Qianjiang city, China. Seven environmental impact categories, including non-renewable energy depletion (NED), global warming potential (GWP), acidification potential (AP), eutrophication potential (EP), human toxicity potential (HTP), freshwater toxicity potential (FTP) and soil toxicity potential (STP) were involved. Results showed that the NED and GWP were primary caused in off-farm stage, but the other environmental impact categories, including AP, EP, HTP, FTP, and STP were mainly occurred in the on-farm stage whether in RM or RCIS. Despite decreased chemical fertilizers and pesticides application in rice growing subsystem, the NED, GWP, AP, EP, HTP and STP were increased in RCIS by 84.30%, 89.37%, 61.88%, 95.87%, 98.06% and 70.78%, respectively, compared with RM. The crayfish farming subsystem produced more resources consumption, pollutant emissions and toxicity potential, with feed production and input being the primarily contributor to environmental impact categories in RCIS. The total environmental impact index from RCIS was 90.95% higher than that from RM. It is worth noting that obviously higher EP was produced in crayfish farming subsystem of RCIS, indicating that pollutant emissions resulted from aquaculture farming might be ignored and hidden in paddy fields. Based on these results, it is suggested that improving aquatic feed utilization, providing necessary technical training and guidance to farmers, and formulating environmental pollution risk control policies and punitive measures might be taken into consideration to ensure the effective use and sustainable development of rice-aquatic animal integrated system.

Strategy development of commodity potato granola (Solanum tuberosom L.) in Tombolo Pao district Gowa Regency

The study aims to describe the granola potato agribusiness in the Tombolopao District; identify strategic issues of granola potato agribusiness to see internal and external conditions and formulate priority strategies for developing granola potato agribusiness in the Tombolopao District Gowa Regency. The research method is descriptive. The farming analysis is IFE, EFE and SWOT analysis. The results show that the potato agribusiness system condition in the of Tombolopao is still not running optimally, due to the non-functioning of the upstream subsystem, where the procurement of production inputs (for granola potato seeds). In the farming subsystem, potato cultivation has provided benefits to farmers. The farming is feasible to be developed with R/C for cash of 3.30. Which means that every rupiah incurred will provide revenue of 3.30, while R/C for the total cost of 3.25. Which means that every rupiah cash incurred will provide 3.25 receipts. In the marketing subsystem. potatoes have been marketed to Kalimantan and Southeast Sulawesi. Prices are determined by collectors. In the downstream (processing) subsystem. Not all of the processed potato entrepreneurs use potatoes as their raw material, which causes new potatoes to be sold in fresh products. In the service and support subsystem, supported by agricultural extension workers, who accompany and provide information related to potato cultivation, but from supporting capital., farmers have not utilized credit provided by financial institutions because they still use private capital. Key internal factors, high demand with a weight of 3.60 is the main strength, and weaknesses are at the level of capital which is still limited with a weight of 2.00 while the external key factor of the opportunity factor that ranks first in the support of the government with a score of 0.22 and weaknesses is in the location of relatively expensive production facilities with a score of 0.18

Cooperation-based partnership model with the partnership of authorities solution for improving broiler agribusiness partnership systems in increasing partner income

This study aims to describe the cooperative-based broiler agribusiness partnership model and the role of the partnership authority as an alternative solution to improve the performance of the broiler agribusiness partnership system in increasing the income of partner farmers. This research was conducted in South Sulawesi with a quantitative descriptive approach based on expert judgment. The results of the study show that the concept of a vertically integrated partnership is not a guarantee of the creation of the expected partnership, as long as the partnership model has the main motive of the business to seek and obtain maximum benefits, the results will not be maximized. The cooperative-based broiler chicken agribusiness partnership model is a partnership development model in which the role of the core company that has been controlled by livestock production facility producers is expected to experience a balance change set by the partnership authority. With the cooperative-based partnership model, the position of farmers who have only been and enjoying income in the farming sub-system will have the opportunity to obtain a share of income in the upstream sector through the distribution of the remaining business results from cooperative membership so that the potential for increased income is wider. Thus theoretically, if the concept runs well, it is expected that it will be a solution to the problem of developing broiler chicken agribusiness partnerships so far that seem unable to be controlled by existing institutions and unable to provide broad income increases for partners and their stakeholders, of course assuming that the concept works ideally with the support of all components involved in it without the intervention of political behavior as has been feared so far where a number of parties accuse political interests playing behind this industry.

KERAGAAN USAHA TANI UBI CILEMBU DALAM RANGKA MENGKOPERASIKAN PETANI

The agribusiness system of Cilembu farming consist of procurement of production facilities subsystem, on farm subsystem, marketing subsystem, subsystem of post harvest and subsystem of support. In this agribusiness system there are problem such as in procurement of production facilities subsystem is limited business capital to purchase production facilities so that the input production such as fertilizer are not always available every season only can be purchased if the previous harvesting business capital has been paid or if they get loans from middleman as well as marketing channels are still long and not favorable to the farmers and the selling price of “ubi Cilembu” is still determined by the middleman therefore the role of union is needed to overcome these problems. So in this case the cooperative can play a role in the cultivation of land that unites the lands of farmers who had small fragmented into one in order to have a large area so that it can produce higher production. If in terms of the scale of production to the results, the sum of all coefficients each shows less than one result, so that the scale of Cilembu cassava production is included inelastis, this role of the cooperative is needed in an effort to increase the production of production in the presence of cooperatives, the cooperative can provide guidance or intensive counseling to the members for cultivation of Cilembu yam cultivation can be increased production results. All respondent “ubi Cilembu” farmers agree with the idea of establishing an union.

Assessing variability in carbon footprint throughout the food supply chain: a case study of Valencian oranges

This study aims to analyse the variability in the carbon footprint (CF) of organically and conventionally produced Valencian oranges (Spain), including both farming and post-harvest (PH) stages. At the same time, two issues regarding sample representativeness are addressed: how to determine confidence intervals from small samples and how to calculate the aggregated mean CF (and its variability) when the inventory is derived from different sources. The functional unit was 1 kg of oranges at a European distribution centre. Farming data come from a survey of two samples of organic and conventional farms; PH data come from one PH centre; and data on exportation to the main European markets were obtained from official secondary sources. To assess the variability of the farming subsystem, a bootstrap of the mean CF was performed. The variability of the PH subsystem was assessed through a Monte Carlo simulation and a subsequent subsampling bootstrap. A weighted discrete distribution of the CF of distribution and end-of-life (EoL) was built, which was also bootstrapped. The empirical distribution of the overall CF was obtained by summing all iterations of the three bootstrap procedures of the subsystems. The CF of the baseline scenarios for conventional and organic production were 0.82 and 0.67 kg CO2 equivalent·kg orange−1, respectively; the difference between their values was due mainly to differences in the farming subsystem. Distribution and EoL was the subsystem contributing the most to the CF (59.3 and 75.7% of the total CF for conventional and organic oranges, respectively), followed by the farming subsystem (34.1 and 19.8% for conventional and organic oranges, respectively). The confidence intervals for the CF of oranges were 0.72–0.92 and 0.61–0.82 kg CO2 equivalent·kg orange−1 for conventional and organic oranges, respectively, and a significant difference was found between them. If organic production were to reach 50% of the total exported production, the CF would be reduced by 5.4–8.4%. The case study and the methods used show that bootstrap techniques can help to test for the existence of significant differences and estimate confidence intervals of the mean CF. Furthermore, these techniques allow several CF sources to be combined so as to estimate the uncertainty in the mean CF estimate. Assessing the variability in the mean CF (or in other environmental impacts) gives a more reliable measure of the mean impact.

Concept of Modal Repulsion for Examining the Subsynchronous Oscillations Caused by Wind Farms in Power Systems

This paper investigates the torsional subsynchronous oscillations (SSOs) of synchronous generators caused by the grid-connected wind farms. The investigation does not rely on the representation of a wind farm by an aggregated wind generator and is based on a multi-input and multi-output closed-loop model. The model is comprised of the wind farm subsystem, which includes all the wind farms, and the subsystem of rest of power system (ROPS). Theoretical analysis proves that the open-loop SSO modal coupling of wind farm subsystem and ROPS subsystem results in the closed-loop SSO modal repulsion on the complex plane. Subsequently, damping of torsional SSOs decreases and growing SSOs may occur when the closed-loop modal repulsion is strong. Hence, closed-loop modal repulsion explains and reveals the mechanism about why the wind farms may cause the torsional SSOs in the power system. In addition, a method of open-loop modal analysis is proposed to detect the SSO instability risk brought about by the wind farms. The detection is based on the estimation of degree of closed-loop modal repulsion and only needs the modal information of open-loop subsystems. An example power system with wind farms is presented to demonstrate analysis and conclusions made in the paper.

Climate change adaptation in Nigerian agricultural sector: A systematic review and resilience check of adaptation measures

The changing climate is adversely affecting the productivity and livelihoods of Nigerian smallholder rural farmers. Several studies predict worsening outcomes for future climate events, for example heat waves, drought and intense precipitation. Farmers are required to adopt several measures to thrive, given the observed or expected climate change events. Existing studies about the interaction between climate change the agriculture sector has focused evaluating the bi-directional causal relationships, and identifying adaptation measures, but research on the climate resilience aspect of these adaptation measures is missing, or at best, low. This study aims to fill this gap in knowledge by assessing resilience and contribution to sustainability of farmer-adopted measures aimed at addressing risks posed by climate change. We conduct a systematic review of 95 studies concentrating on climate adaptation by smallholder rural farmers in Nigeria in the period 2010 to 2019. We assess the climate resilience of adaptation measures using the Ifejika-Speranza Resilience Check Toolkit. Our findings show that farmers are using climate-resilient adaptation measures; however, we could not ascertain how these have led to sustainable agricultural systems, since it is not the focus of the current study. Our findings show that majority of the adaptation studies in Nigeria are focused on crop farming subsystem. The major agricultural ecosystems and the broad adaptation areas are: Crop farming (improved soil and land management, crop-specific Innovation, water management practices, climate information services and education, access to finance, and off-farm diversification), livestock farming (improved livestock management systems, improved breeding strategies, sustainable health improvement, proper feed formulation early maturing and heat-resistant bird varieties), and fish farming (water harvesting measures, organic material, quick-maturing varieties).