• 한국수자원학회논문집
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• 제55권7호
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• pp.515-529
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• 2022

이용 가능한 수자원의 규모를 파악하는 것은 지속가능한 이수계획 수립에 필수적인 과정이다. 특히 댐 시설은 용수를 저류하여 갈수기에 공급하기 위한 주요 수공 시설물로써 댐 유입량 및 댐 운영 방안에 따라 댐의 용수공급능력은 크게 달라질 수 있다. 국내에서는 과거 유입량 관측자료를 바탕으로 저수지 운영모의 방법을 통해 댐 용수공급능력을 산정하고 있으며, 이때 관측기간 내 가뭄발생 여부에 따라 용수공급능력이 과소 혹은 과다 추정되는 불확실성을 내포하며, 이는 수자원 계획 수립의 신뢰도를 저해하는 요인이 될 수 있다. 본 연구에서는 발전용댐의 용수공급능력 적정 범위를 산정하기 위해 확률론적 유입량 자료를 활용하였다. 즉, 다양한 기후 및 사회경제 변화를 반영한 확률론적 댐 유입량 및 이를 활용한 발전용댐 용수공급능력의 범위를 산정하는 방법을 제시하였으며, 국내 한강수계에 위치한 발전용댐을 대상으로 분석을 수행하였다. 향후 기후변화에 대응하기 위한 발전용댐의 용수공급능력 파악은 더욱 중요해질 것으로 예상되며, 본 연구 결과는 다양한 기후 시나리오에서의 댐 용수공급능력 범위를 정량적으로 파악함으로써 국내 수자원 계획 수립에 기여할 것으로 기대된다.

• 한국작물학회지
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• 제48권6호
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• pp.452-459
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• 2003

땅콩의 완전종실생산을 위해서는 150-180일의 생육기간이 소요되나 풋땅콩용으로 출하하면 총생육일수를 20-30일 정도 단축할 수 있을 뿐만 아니라 수확후 지상부 잔존유기물도 많이 남게 된다. 땅콩재배기간 단축에 따른 풋땅콩-무, 보리, 마늘과의 relay-cropping system에서 수확후 잔존 유기물의 토양환원 유무에 따른 각 작물들의 생육과 토양의 이화학성, 미생물상의 변화양상에 관한 기초자료를 얻어 남부지역 풋땅콩 안정생산기술을 확립하고자 수행한 시험결과를 요약하면 다음과 같다. 1. 작부체계별 시험후 토양경도는 풋땅콩 단작에서 가장 높았고, 토양 공 극율은 풋땅콩 단작 대비무, 보리, 마늘과 2모작 작부체계 처리에서 높 았으며 수확후 잔존유기물을 환원하였을 때 더욱 높아졌다. 2. 단작의 풋땅콩은 보리, 마늘과 2모작 작부체계상에서 재배된 풋땅콩에 비하여 도복 및 병 발생이 심하였다. 작부체계별 풋땅콩 수량은 단작에 비하여 풋땅콩-보리 및 풋땅콩-마늘 작부체계에서 증수하였으나, 유기 물 환원에 따른 수량 차이는 없었다. 3. 풋땅콩 후작의 마늘과 보리의 수량은 유기물 환원에 의하여 증대되었다. 4. C/N율이 높은 보리짚의 토양 환원에서 질소무기량이 증가하였고, 풋땅콩-보리와 풋땅콩-마늘의 작부체계에서 Pseudomonas spp.균 및 Trichoderma spp.균의 밀도가 높아져 풋땅콩의 친환경 작부체계로 추정되었다

• 한국토양비료학회지
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• 제45권2호
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• pp.156-161
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• 2012

Marine biomass is considered an important substrate for anaerobic digestion to recovery energy i.e. methane. Nevertheless, marine biomass has attracted little attention by researchers compared to terrestrial feedstock for anaerobic digestion. In this study, biochemical methane potential (BMP) test was used to evaluate generation of renewable energy from starfish. A cumulative biogas yield of $748{\pm}67mL\;g^{-1}VS^{-1}$ was obtained after 60 days of digestion. The cumulative methane yield of $486{\pm}28mL\;CH_4\;g^{-1}VS^{-1}$ was obtained after 60 days of digestion. The methane content of the biogas was approximately 70%. The calculated data applying the modified Gompertz equation for the cumulative $CH_4$ production showed good correlation with the experimental result obtained from this batch study. Since the result obtained from this study is comparable to results with other substrates, marine biomass can be co-digested with food waste or swine wastewater to produce $CH_4$ gas that will help to reduce the gap in global energy demand.

• 한국작물학회지
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• 제45권2호
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• pp.73-78
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• 2000

This study was conducted for 2 years at Chinju region to establish suitable seeding rate and fertilizing levels of nitrogen, phosphorous and potassium in spring-sown Jinyangbori. Heading and maturing were delayed by increasing fertilizers, especially nitrogen. Number of spikes per were secured by much seeding and increased application of nitrogen. One thousand grain weight reduced with increasing fertilization at any seeding rate. Relatively high harvest indices were observed with 12-10-4 at 10kg. 10a$^{-l}$ seeds planted, followed by 6-10-8 at 15 kgㆍ 10a$^{-1}$, and 6-10-4kgㆍ 10a$^{-l}$ at 20kg ㆍ 10a$^{-l}$ of N-P-K fertilizing combinations, respectively. There was no distinct differences on yield for various seeding rates in spring-sown barley. When seeding rate increased up to 15kgㆍ10a$^{-1}$, the positive effect of fertilizers was recognized as the function of balanced-application. It was possible to recommend 10kgㆍ10a$^{-1}$ as seeding rate and 6-5-4(N-P-K)kgㆍ10a$^{-1}$ as fertilizing combination in spring-time seeding considering low input and sustainable agriculture. There was no significant difference of protein content in grain by seeding rate. Increase of nitrogen fertilizer enhanced protein content in grain.

• Ocean and Polar Research
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• 제27권3호
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• pp.323-333
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• 2005

The paper is to serve as a guide for deciding on a desirable direction for the vessel buyback program, reviewing their performance and economic effects from fish harvest reduction due to not reaching MSY. Compared with maximum willingness to pay for vessel buyback programs designed to avoid economic losses occurring as a result of overfishing, the portions of investment costs for buyback program are so small comparatively to the range of 0.32% to 12.19% at the annual base. The economic loss effects occurred in terms of the reduction of fishing harvest are comprehensively estimated at the present value of 30,877 billion won since 1971, and exceeded the revenues for fish harvests from 1999. In order to resole fish stocks through a vessel buyback program, this paper recommends that the yield should be reduced to less than the intrinsic growth rate. Otherwise, the buyback program policy eventually fails regardless of the temporal effect of benefits. This paper further argues that technical policy tools such as fishing grounds, fishing seasons, size of fish and minimum size of meshes should be effectively utilized.

• Environmental Engineering Research
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• 제22권3호
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• pp.288-293
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• 2017

In this study, we report the industrial application of an efficient technology for the recovery of gallic acid from Chinese nutgall processing wastewater. The recovery of gallic acid by industrial scale extraction and stripping devices was performed, with tributyl phosphate as the extractant and kerosene as the diluent. The results showed that the theoretical extraction stage was four, while the theoretical stripping stage was two. A closed-cycle system was studied for the continuous countercurrent extraction and stripping, with a five-stage extraction device and a three-stage reflux stripping device. The results showed that the multistage extraction-stripping system could steadily run for a long period, the average gallic acid level in the raffinate was $0.85g{\cdot}L^{-1}$, and the gallic acid content recovered in the strip liquor was higher than $120g{\cdot}L^{-1}$. The average extraction yield of gallic acid was 94.14%. When the strip liquor was used as raw material for production, the average production yield increased by 8.64%. In addition, after extraction, the $COD_{Cr}$ in the wastewater decreased by 38.19%, and the biodegradability of wastewater improved by 1.6 times. This study provided a new impetus for the sustainable development of the Chinese nutgall processing industry.

• Ocean and Polar Research
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• 제37권2호
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• pp.161-177
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• 2015

This study analyzes the stock assessment of yellow croaker caught mainly by the Korean stow net and gill net fisheries focusing on single species and multiple fisheries. This study standardizes fishing efforts for the two fisheries using the general linear model and uses a surplus production model based on the exponential growth model. The Clarke Yoshimoto Pooley model estimates a maximum sustainable yield(MSY), an allowable biological catch(ABC), fishing efforts for MSY($E_{MSY}$) and for ABC($E_{ABC}$). The bio-economic model is used to estimate the maximum economic yield(MEY) and fishing efforts for MEY($E_{MSY}$). Also, the study employs an economic analysis to estimate the economic interaction between stow net and gill net fisheries. The economic analysis shows the profit accruing to the two fisheries from estimated ABC. Finally, the study compares TACs based on single species and single fishery to TAC based on single species and multiple fisheries. The study proposes that the TAC assessment is necessary for single species and multiple fisheries in order to preserve resources.

• 한국패류학회지
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• 제28권2호
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• pp.109-116
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• 2012

In order to understand the effect of introduction of oyster rack culture on natural short-necked clam, Ruditapes philippinarum, stock, we investigated the status of natural clam stock prior to introduction of oyster rack culture at Yeongheung Coast of Wando Island. The growth equation of the clam was estimated as: $L_t=61.46{\cdot}(1-e^{-0.172(t+0.155)})$ from ring radius composition of shell. Instantaneous coefficient of total mortality and natural mortality were calculated as: 2.4087/year and 0.478/year, respectively. The age at first capture was estimated to be 2.55 year. The total biomass was estimated to 3.23 ton in the bed (0.8 ha). Applied by these parameters, the annual recruit biomass and the current yield per recruit (Y/R) was corresponded to $114.7individuals/m^2$ and $92.0g/m^2$, respectively. Maximum sustainable yield (MSY) was estimated 0.77 ton/year which was close to annual catches, 0.74 ton/year, in the area.

• 한국수산과학회지
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• 제57권3호
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• pp.292-301
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• 2024

It is challenging to simultaneously estimate parameters in a stock-recruitment relationship, steepness, and natural mortality rate with the other parameters within an age-structured assessment model even in a data-rich situation. Such a problem leads to uncertainty in estimates of management references such as maximum sustainable yield (MSY), which are affected by those components. The objective of this study was to evaluate the effects of those parameters on MSY by analyzing the process of estimating the MSY. For illustration, we used two data sets: The chub mackerel Scomber japonicus in the Korean waters and the yellowtail flounder Limanda ferruginea in the Southern New England-Mid Atlantic. As a result, the natural mortality rate influenced spawning stock biomass per recruit, yield per recruit, and MSY, while steepness affected MSY. A sensitivity analysis enabled us to estimate the natural mortality rate and steepness. The optimal set of steepness and natural mortality was 1.0 and 0.37 per year for the chub mackerel, and 0.35, and 0.8 per year for the yellowtail flounder, respectively.

• 한국산림과학회지
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• 제103권2호
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• pp.264-269
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• 2014

본 연구는 아까시나무 군락에 대한 현재 생육지 분포면적의 파악과 임분수확량 및 탄소저장량을 구명하기 위하여 수행되었다. 아까시나무에 대한 분포면적은 1:5,000 임상도를 이용하여 추출하였으며, 임분수확량은 Weibull 직경분포모델을 이용하였고, 탄소저장량 및 흡수량은 임분수확량에 탄소배출계수를 적용하여 산출하였다. 임분수확량을 산출하기 위하여 임분 평균직경, 임분 흉고단면적, 최소 및 최대 직경 등 임분 생장인자에 대한 추정식을 산출하고 정확성을 검증하였다. 이 결과 모든 생장인자의 추정식이 분석에 이용할 수 있는 유의성을 가지고 있는 것으로 나타났다. 또한 임지의 생산력을 판정할 수 있는 지위지수를 도출한 바, 지위지수는 16~22 범위에 있는 것으로 나타났으며, 이들을 종합하여 임분수확표를 만들었다. 우리나라 아까시나무는 경상, 충청 및 경기도의 내륙에 주로 분포하는 것으로 나타났으며, 총 면적은 26,770 ha에 달하는 것으로 나타났다. 이를 탄소저장량으로 전환한 결과 2,517,598 tC 였으며, 연간 3.76 tC/ha를 흡수하는 것으로 계산되었다. 이는 탄소흡수량이 높은 수종으로 알려져 있는 참나무류와 유사하여, 추후 아까시나무가 기후변화 시대에 온실가스를 저장하는 수종으로서의 역할도 충분히 가능할 것이라 판단된다. 또한 본 연구에서 만든 임분수확표는 아까시나무 경영 및 관리정책에 도움을 줄 수 있을 것으로 사료된다.