• 한국토양비료학회지
• /
• 제46권3호
• /
• pp.187-192
• /
• 2013

This study was carried out to investigate the incorporation effect of green manure crops (GMC) such as the hairy vetch on improvement of soil environment in reclaimed land during silage corn cultivation over the past two years. Plots consisted of conventional fertilization (CF) and incorporation of GMC were divided by addition rate of nitrogen fertilizer (100 kg $ha^{-1}$) with 30 - 100% of non nitrogen fertilization (NNF). Soil physico-chemical properties and growth and yield potential of silage corn were examined. The tested soils showed strong alkali and saline properties with low contents of organic matter and available phosphate while contents of exchangeable sodium and magnesium were high. Soil salinity increased during cultivation of summer crop. However, corn was not affected by salt content. The fresh weight of GMC at incorporation time was 18,345 kg $ha^{-1}$. Content of total nitrogen was 3.09% and the C/N ratio was 12.8 at incorporation time. Fresh and dry matter yield of silage corn were higher in the order of N30% reduction, CF, N50% reduction, N70% reduction, N100% reduction and NNF. Fresh and dry matter yield potential of silage corn for N30% reduction were comparable to those of CF. Bulk density of the soil decreased with incorporation of GMC, while porosity was increased. The soil pH decreased while content of exchangeable calcium, available phosphate, and organic matter increased. Also contents of exchangeable sodium and potassium decreased with incorporation of GMC. The data indicate that incorporation of hairy vetch can improve soil physical and chemical properties and reduce nitrogen fertilizer application especially for alkali saline reclaimed soil such as Saemangeum reclaimed land.

• 한국토양비료학회지
• /
• 제45권6호
• /
• pp.955-960
• /
• 2012

신간척지 토양 pH는 7.5 이상의 알카리성 토양으로 요소와 같은 화학비료 처리 시 휘산에 의한 손실이 증가하여 비료효율이 저감된다. 한편 퇴비와 같은 유기태질소를 함유하는 유기질비료를 처리하더라도 토양 내 Nitrosomonas나 Nitrobactor와 같은 미생물상이 미약하여 질산화과정이 미약하여 실질적 유기질비료의 효과를 기대하기 어렵다. 한편 논과 같이 초기부터 담수상태로 시작하는 토양에서는 식물체가 질소원을 양분으로 이용하기 전 탈질화과정을 거치거나 아니면 용탈과정을 통하여 손실이 발생한다. 따라서 토양 pH가 7.5 이상으로 증가함에 따라 요소형태로 토양에 가해진 질소원으로부터 암모니아가스 발생이 급격히 증가되면 실질적 질소질 비료의 이용효율이 저하된다. 따라서 pH7 이상의 간척지 토양에 요소를 질소원으로 처리 시 암모니 움태나 질산태 형태의 가급태 질소원은 매우 적을 것으로 추정된다. 그러므로 담수하에서의 간척지 토양의 산화환원 특성과 토양 pH에 따른 처리 비종과 처리 기술개발이 반드시 필요하다고 판단한다.

• 한국토양비료학회지
• /
• 제28권4호
• /
• pp.327-333
• /
• 1995

슬러시 처리구에서 수수와 1수립수의 증가에 기인하여 현미수량이 청도 10%, 진주 15%, 여천 7% 증가하였다. 슬러지 처리구에서 현미증 규산의 함량이 높았다. 벼 재배시 레미콘 슬러지를 34.8톤/ha 수준에서 처리하면 토양의 pH상승효과가 크고, 석회자원과 칼리공급원으로서의 이용 가능성이 큼을 알 수 있었다. 그러나 여천의 간척지 토양에 슬러지를 시용할 경우 pH 7.2 이상으로 알칼리 반응을 나타내고 토양의 고상율을 증가시키므로 레미콘 슬러지의 사용에 신중을 기해야 할 것으로 판단된다.

• 한국조경학회지
• /
• 제34권3호
• /
• pp.79-90
• /
• 2006

Tamarix chinenis blooms twice a you and its flowers, branches and leaves make the adjustment of tree shape. Propagation methods and growth characteristics of T. chinensis were studied in order to ascertain its potential use as one of vegetation resources for coast forestation and landscaping. The study results indicated that 1 or 2 you old hard wood cuttings showed higher rooting ratio than greenwood or semi hard wood cuttings. One to one mixture between vermiculite and pearlite appeared to be the best for bed soil, and sea sand and silt(loess) mixture was the next. Sea sand and granitic soil followed after. In terms of seasonal differences, spring cuttings showed the best rooting ratio, root number, and root length. Fall cuttings followed after spring cutting, and summer cuttings showed worst results regarding rooting ratio, root number, and root length. The best rooting promotion effects of growth regulators were observed with sea sand bed soils. There was no significant difference among growth regulators in terms of rooting and shoot growth. Low concentration below 100 ppm of growth regulators was enough for rooting promotion effect. In general, the number and mean length of roots and shoots were showed the excellent records in the sites with high rooting ratio. The study result strongly showed that T. chinensis can be considered as a suitable tree for coast forestation and landscaping because of its easy cutting propagation and rapid growth on saline lands.

• Journal of Microbiology and Biotechnology
• /
• 제18권12호
• /
• pp.1966-1974
• /
• 2008

A typical tropical soil from the northeast of Brazil, where an important terrestrial oil field is located, was accidentally contaminated with a mixture of oil and saline production water. To study the bioremediation potential in this area, molecular methods based on PCR-DGGE were used to determine the diversity of the bacterial communities in bulk and in contaminated soils. Bacterial fingerprints revealed that the bacterial communities were affected by the presence of the mixture of oil and production water, and different profiles were observed when the contaminated soils were compared with the control. Halotolerant strains capable of degrading crude oil were also isolated from enrichment cultures obtained from the contaminated soil samples. Twenty-two strains showing these features were characterized genetically by amplified ribosomal DNA restriction analysis (ARDRA) and phenotypically by their colonial morphology and tolerance to high NaCl concentrations. Fifteen ARDRA groups were formed. Selected strains were analyzed by 16S rDNA sequencing, and Actinobacteria was identified as the main group found. Strains were also tested for their growth capability in the presence of different oil derivatives (hexane, dodecane, hexadecane, diesel, gasoline, toluene, naphthalene, o-xylene, and p-xylene) and different degradation profiles were observed. PCR products were obtained from 12 of the 15 ARDRA representatives when they were screened for the presence of the alkane hydroxylase gene (alkB). Members of the genera Rhodococcus and Gordonia were identified as predominant in the soil studied. These genera are usually implicated in oil degradation processes and, as such, the potential for bioremediation in this area can be considered as feasible.

• 한국농공학회논문집
• /
• 제65권1호
• /
• pp.73-81
• /
• 2023

To understand salinity status of fresh water and paddy soils and the susceptibility of rice to salinity stress of Gunnae reclaimed tidelands, salinity monitoring was conducted in rainy and dry seasons. For fresh water, a high salinity was observed at the sampling location near the sluice gate and decreased with distance from the gate. This spatial pattern of fresh water salinity indicates the necessity of spatial distribution of salinity in the assessment of salinity status of fresh water. Interestingly, there was significant correlation between rainfall amount and salinity, implying that salinity of fresh water varies with rainfall and thus it may be possible to predict salinity of water using rainfall. Soil salinity also higher near the gate, reflecting the influence of high saline water. In addition, the groundwater salinity also high to threat rice growth. Though soil salinity status indicated low possibility of sodium injury, there was changes in soil salinity status during the course of rice growth, suggesting that more intensive monitoring of soil salinity may be necessary for soil salinity assessment. Our study suggests the necessity of intensive salinity monitoring to understand the spatio-temporal variations of salinity of water and soil of reclaimed tideland areas.

• 한국토양비료학회지
• /
• 제19권4호
• /
• pp.327-332
• /
• 1986

pH7 인산완형용액(燐酸緩衡容液)으로 추출(抽出)한 지력질소(地力窒素)를 몇개의 토양(土壤)에서 비교평가(比較評價)하기 위(爲)하여 퇴비(堆肥), 석회(石灰) 및 규회석(珪灰石)을 32년간(年間) 장기연용(長期連用)한 사질답(砂質畓), 이앙전(移秧前) 70일간(日間) 담수(湛水) 및 무담수(無湛水)한 사질답(砂質畓), 다수확(多收穫)을 낸 보통답(普通畓) 및 인접(隣接)한 농가(農家)의 보통답(普通畓)을 실내조건(室內條件)으로 지력질소평가(地力窒素評價), 지력질소소장(地力窒素消長), 지력질소(地力窒素)와 추출질소(抽出窒素)와의 관계(關係) 및 답유형별(畓類型別) 지력질소(地力窒素)에 의(依)한 질소시비량결정(窒素施肥量決定) 등(等)을 분석검토(分析檢討)하였던 바 다음과 같은 결과(結果)를 얻었다. 1. 동일비료(同一肥料)를 연용(連用)할 사질답(砂質畓)에서 처리별(處理別) 인산완형액(燐酸緩衡液)에서 추출(抽出)된 유기태질소(有機態窒素)는 3요소(要素)+퇴비구(堆肥區), 3요소구(要素區), 3요소(要素)+퇴비(堆肥)+석회(石灰)+규회석구(珪灰石區), 3요소(要素)+석회(石灰)+규회석구(珪灰石區), 3요소(要素)+규회석(珪灰石), 무비구(無肥區) 순위(順位)로 많았다. 2. 3요소(要素) 및 3요소(要素)+퇴비구(堆肥區) 처리(處理)에서 생육시기별(生育時期別)로 지력질소(地力窒素) 소장(消長)을 보면 처리(處理)에 관계(關係)없이 시험전(試驗前)에 비(比)해 유수형성기(幼穗形成期), 출수기(出穗期)로 생육(生育)이 경과(經過)됨에 따라 유기태질소함량(有機態窒素含量)은 감소(減少)되는 경향(傾向)이었다. 3. 다수확(多收穫)을 낸 보통답(普通畓)과 인근보통답(隣近普通畓)에서 비교(比較)할때 T-N, Org-N, $NH_4-N$ 성분(成分)은 다수확답(多收穫畓), $NO_3-N$는 인근답(隣近畓)에서 많았다. 특(特)히 4주간(週間) 담수항온후(湛水恒溫後) 생성(生成)된 $NH_4-N$와 추출(抽出)된 전질소(全窒素)N와는 1%의 유의성(有意性)이 있는 정(正)의 관계(關係)가 있었다. 4. 담수(湛水) 및 무담수(無湛水)한 사질답(砂質畓)에서 토양유기태질소(土壤有機態窒素)는 무담수처리구(無湛水處理區)에서 많았으나 도체내(稻體內) 질소흡수량(窒素吸收量)은 반대(反對)로 담수구(湛水區)에서 많았다. 5. 답유형별(畓類型別) 토양(土壤)의 추출전질소(抽出全窒素)는 보통답(普通畓), 사질답(砂質畓), 미숙답(未熟畓), 염해답(鹽害畓) 순(順)으로 많았으며 지력질소(地力窒素)에 의(依)한 추정질소시비량(推定窒素施肥量)은 반대(反對)로 염해답(鹽害畓), 미숙답(未熟畓), 사질답(砂質畓), 보통답(普通畓) 순위(順位)였다.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2017년도 9th Asian Crop Science Association conference
• /
• pp.316-316
• /
• 2017

The objective of this study is to estimate quantitatively soil salinity and soil loss at upland soils in agriculture land region in Saemangeum reclaimed land on the south Korea coasts. Soil loss and soil salinity are the most critical problem at reclaimed tidal saline soil in Korea. The several thematic maps of research area such as land cover map, topographic and soil maps, together with tabular precipitation data used for soil erosion and soil salinity calculation. Meteorological data were measured directly as air temperature, wind speed, solar radiation, and precipitation. The experiment was conducted 2% sloped lysimeter ($5.0m{\times}20.0m$) with 14 treatments and it were separated by low salinity division (LSD) and high salinity division (HSD) install. The cation content in ground water increased during time course, but in the case of land surface water the content was variable, and $K^+$ was lower than that of $Na^+$ and $Mg^{2+}$. At the LSD under rainproof condition, the salinity was directly proportional to soil water content, but at the HSD the tendency was no reversed. In condition of rainproof, the amount of soil salinity was higher at the HSD than at the LSD. Positive correlation was obtained between the soil water content and available phosphorous content at the rainfall division, but there was no significance at the surface soil of the rainproof division. Sodium adsorption ratio and anion contents in soil were repressed in the order of vinyl-mulching > non-mulching > bare field. According to the result of analyzing soil loss, soil loss occurred in a vinyl-mulching, a non-mulching and a bare field in size order, and also approximately 11.2 ton/ha soil loss happened on the reclaimed land area. The average soil loss amount by the unit area takes place in a non-mulching and bare field a lot. Our results indicate that soluble salt control and soil erosion are critical at reclaimed tidal saline soil and the results can provide some useful information for deciding management plans to reduce soil loss and salt damage for stable crop production and diverse utilization or cultivation could be one of the management options to alleviate salt damage at reclaimed tidal saline soil in Korea.

• Journal of Plant Biotechnology
• /
• 제7권1호
• /
• pp.1-15
• /
• 2005

Salinity is one of the major limiting factors for agricultural productivity. In plants, accumulation of osmolytes plays a pivotal role in abiotic stress tolerance. Likewise, exclusion or compartmentation of $Na^+$ ions into vacuoles provides an efficient mechanism to avert deleterious effects of $Na^+$ in the cytosol. Both vacuolar and plasma membrane sodium transporters and $H^+-ATPases$ can provide the necessary ion homeostasis. A variety of crop plants were engineered with respect to the synthesis of osmoprotectants and ion-compartmentation, but there are other cellular pathways involved in the salinity responses that are still not completely explored. Genomics approaches are increasingly used to identify genes and pathway changes involved in salt-tolerance. The new knowledge may be used via guided genetic engineering of multiple genes to create crop plants with significantly increased productivity in saline soils. This review surveys how plants deal with high salt conditions and how salt tolerance can be improved by transgenic approaches.

• Asian-Australasian Journal of Animal Sciences
• /
• 제21권11호
• /
• pp.1599-1603
• /
• 2008

Sodium is involved in elevation of oxalate content in some plant species and this element is abundant in saline soils. Oxalate causes precipitation of insoluble calcium oxalate in the rumen and kidneys. The intention of this study was to evaluate the effect of soil salinity stress on dry matter yield and oxalate content in pot-grown napiergrass (Pennisetum purpureum Schumach). Plants were cut three times at 56, 118 and 179 d after transplanting to the pots. Five salinity treatments were used containing various concentrations of NaCl solution as follows: 0, 100, 300, 600 and 900 mM. At 28, 42, 84, 98, 146 and 160 d after transplanting, plants were irrigated with one liter of the particular treatment for each application. Dry matter yield of napiergrass was not affected (p>0.05) by salinity treatments. Plants treated with 100 mM NaCl exhibited a higher soluble oxalate content compared to other treatments, but the differences were not statistically significant (p>0.05). Although salinity treatments had significant (p<0.05) effects on insoluble and total oxalate contents in plant tissue between the 100 and 900 mM NaCl treatments, the differences were too small to be considered biologically important. The present study indicates that where the soil is high in NaCl, napiergrass will tend to grow well and be low in oxalate.