• 한국농림기상학회지
• /
• 제7권1호
• /
• pp.4-14
• /
• 2005

CarboKorea and HydroKorea are the domestic projects aiming to improve our understanding of carbon and water cycles in a typical Korean forest located in a complex terrain with a watershed connected to large rivers. The ultimate goal is to provide a nowcasting of these cycles for the whole Peninsula. The basic strategy to achieve such goal is through the inter- and multi-disciplinary studies that synthesize the in-situ field observation, modeling and remote sensing technology. The challenge is the fact that natural ecosystems are nonlinear and heterogeneous with a wide range of spatio-temporal scales causing the variations of mass and energy exchanges from a leaf to landscape scales. Our paradigm now shifts from temporal variation at a point to spatial patterns and from spatial homogeneity to complexity of water and carbon at multiple scales. Yet, a large portion of our knowledge about land-atmosphere interactions has been established based on tower observations, indicating that the development of scaling logics holds the key to the success of CarboKorea and HydroKorea. Here, we review the pioneering work of FIFE (First ISLSCP Field Experiment) on scaling issues in a temperate grassland and discuss the lessons from it for the application to Gwangneung forest site.

• 한국초지조사료학회지
• /
• 제13권2호
• /
• pp.93-98
• /
• 1993

To determine the effects of potassium($K_2O$) fertilization level(0, 100, 200 and 300 kg/ha/year) on the growth, dry matter(DM) yield, nutritive value and nitrate nitrogen($NO_3$-N) concentration of grasses grown under shading condition, this experiment was carried out in Grassland Div., LES, 1989. The plants were sampled on different growing seasons (spring, summer and autumn) and growth stages (grazing and soiling), respectively. Shade was controlled artificially ca. 45-50%, and the level of nitrogen fertilization was 200 kg/ha/year in all treatments. Higher DM was produced in spring 1, 453 kg at grazing and 2, 364 kg/ha at soiling stage, and DM production was increased with increasing level of $K_2O$. In this experiment, the optimum amount of $K_2O$ fertilizer was 200 kg/ha. The neutral detergent fiber, acid detergent fiber, DM digestibility, and relative feed value of grasses were not affected by $K_2O$ fertilization, regardless of growing season and growth stage. The $NO_3$-N concentration of grasses grown in spring was very low (ca. 1.0%), regardless of growth stage and $K_2O$ level. However, $NO_3$-N concentration was very high in summer and autumn season, also $NO_3$-N was decreased significantly with increasing level of $K_2O$ fertilization (P<0.05). Application of $K_2O$ fertilizer, therefore, is thoughs to be desirable for reducing $NO_3$-N concentration of grasses, especially in summer and autumn season. So annual split fertilization of $K_2O$ could be recommended on woodland pasture.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
• /
• pp.673-678
• /
• 2002

A satellite remote sensing is useful for vegetation monitoring. But it has some problem. One of these, it is difficult to find a difference of vegetation surface roughness using satellite remote sensing. Each vegetation type has unique surface roughness, for example needle leaves forest, broad leaves forest and grassland. Difference of vegetation surface roughness can be detected by satellite multiangular observation. In this study, objective is to propose index of vegetation surface roughness using BRF property. General vegetation indices are calculated from nadir data of satellite data. A proposed index is calculated from two different observation zenith angle data. Two different zenith data can provide BRF (Bi-directional Reflectance Factor) property of satellite observation data. A proposed index was able to detect different value on where NDVI shows similar high value areas of rice field and forest. This index is useful for vegetation monitoring.

• 한국초지조사료학회지
• /
• 제5권1호
• /
• pp.33-36
• /
• 1985

牧場에 林間栽培함에 있어서 閉度의 多少가 牧草의 生育 및 收量에 미치는 影響을 究明코자 리기데타 人工造林地의 閉度를 0(露光區), 25, 50, 75%로 調節하여 Orchard grass를 栽培하였던 바 그 結果는 다음과 같다. 1 林地內의 Orchard grass의 葉面積은 各 刈取時期 모두 閉度 25, 0, 50, 75%區의 順位이며 特히 閉度 25%區는 0%區에 비하여 有意的인 增加傾向 이었다. 2. Orchard grass의 草長은 閉度가 높을수록 伸長하는 傾向이나 閉度 0%區와 25%區 間에는 差異를 認定할 수 없었다. 3 閉度의 差異에 따른 草長과 葉面積의 關係는 負의 利關關係를 나타내었다. 4. 林地內의 Orchard grass 年間 總 乾物收量은 페도 25%구가 露光區 에 비하여 有意的인 增收效果가 있었으며 50%區는 露光區에 비하여 약간 減少하는 傾向을 나타내었으나 統計的인 有意性은 認定되지 않았다. 그러나 閉度 75%區는 露光區에 비하여 有意的인 減收를 나타내었다.

• 한국농림기상학회지
• /
• 제3권3호
• /
• pp.163-170
• /
• 2001

본 연구는 평택 지역에 대한 Landsat TM 인공위성 자료를 이용하여 평택지역의 토지피복분류도를 만들고 DGPS, 항공사진, 지형도 등을 이용하여 보다 정확한 참조자료를 만들어 분류도의 정확성을 평가하고자 하였다. 논, 밭 등 12개 항목으로 분류하여 면적을 산출한 결과 1997년 6월 현재 평택시의 논면적은 16,157$\textrm{km}^2$, 밭면적은 4,949$\textrm{km}^2$로 나타났다. DGPS, 항공사진, 지형도 등을 이용하여 평가한 결과 간석지, 논, 물 및 바다 등이 90%의 정확도를 보였으며, 밭, 비닐, 산림, 초지, 촌락 등은 낮게 평가되었다. 전체 정확도는 85.8%로 비교적 양호하게 평가되었으며, 논의 경우 92%의 높은 정확도가 나와 원격탐사 자료의 효용성이 큼을 알 수 있었다. 해양, 수역, 도심지 등의 분류결과는 높게 나타났는데 반해 밭, 비닐하우스, 초지 등은 적은 면적으로 혼재되어 있기 때문에 분류 결과가 낮았다.

• Journal of Ecology and Environment
• /
• 제41권2호
• /
• pp.34-44
• /
• 2017

Background: Monitoring terrestrial vegetation cover condition is important to evaluate its current condition and to identify potential vulnerabilities. Due to simplicity and low cost, point intercept method has been widely used in evaluating grassland surface and quantifying cover conditions. Field-based digital photography method is gaining popularity for the purpose of cover estimate, as it can reduce field time and enable additional analysis in the future. However, the caveats and uncertainty among field-based vegetation cover estimation methods is not well known, especially across a wide range of cover conditions. We compared cover estimates from point intercept and digital photography methods with varying sampling intensities (25, 49, and 100 points within an image), across 61 transects in typical steppe, forest steppe, and desert steppe in central Mongolia. We classified three photosynthetic groups of cover important to grassland ecosystem functioning: photosynthetic vegetation, non-photosynthetic vegetation, and bare soil. We also acquired normalized difference vegetation index from satellite image comparison with the field-based cover. Results: Photosynthetic vegetation estimates by point intercept method were correlated with normalized difference vegetation index, with improvement when non-photosynthetic vegetation was combined. For digital photography method, photosynthetic and non-photosynthetic vegetation estimates showed no correlation with normalized difference vegetation index, but combining of both showed moderate and significant correlation, which slightly increased with greater sampling intensity. Conclusions: Results imply that varying greenness is playing an important role in classification accuracy confusion. We suggest adopting measures to reduce observer bias and better distinguishing greenness levels in combination with multispectral indices to improve estimates on dry matter.

• 한국초지조사료학회지
• /
• 제4권2호
• /
• pp.108-114
• /
• 1983

Lycopodium serratum이 우점된 곳에서는 심한 영향을 받았다. 선점식생(先占植生)에 따른 겉뿌림 초종(草種)의 반응은 시일(時日)이 경과함에 따라 Orchardgrass, Perennial ryegrass 및 Ladino clover와 같은 $2{\sim}3$개의 초종(草種)으로 식생(植生)이 단순화(單純化)되는 경향이었고 Orchardgrass가 우점종(優占種)이었다. 식생변화(植生變化)는 예취회수(刈取回數)에 따라 선점식생(先占植生)은 현저히 감소되었고 반면에 목초식생(牧草植生)은 급격히 증가경향을 보였다. 이상의 결과로 보아 겉뿌림 임간초지조성시(林間草地造成時) 선점식생(先占植生)인 Miscanthus sinensis와 Festuca ovina가 우정된 곳의 초지(草地) 개량(改良)은 용이한 편이나, Lycopodium serratum 우점지는 지표처리(地表處理)없이 개량이 어렵다고 보며 개량방법(改良方法)도 낮은 잠재생산성(潛在生産性)에 적합(適合)해야 될 것으로 본다.

• 한국지형학회지
• /
• 제20권1호
• /
• pp.11-20
• /
• 2013

충남 아산 곡교천 유역에 있어서 최종빙기 최성기~만빙기의 기후 및 식생환경을 밝히기 위하여 아산 장재리 지역의 곡저평야 충적층을 대상으로 화분분석을 실시하였다. 시료채취지점은 현재 낙엽활엽수림대(냉온대 남부)에 포함된다. 그 결과는 다음과 같다. (1) 조사지역의 약 19,300-14,100yrB.P.의 식생환경은 크게 YJ-I 기(期)와 YJ-II 기(期)로 구분되며, YJ-Ia 기(期)는 다시 YJ-Ia 기(期)와 YJ-Ib 기(期)로 세분된다. YJ-Ia 기(期)(19,300-17,500yrB.P.)는 최종빙기 최성기에 대비되며 당시의 식생은 삼림에 비해 초지의 분포역이 상대적으로 약간 넓으며 이 시기의 삼림식생은 침활혼합림이다. YJ-Ib 기(期)(15,400-14,750yrB.P.)는 만빙기(또는 최종빙기 최성기)에 대비되며 YJ-Ia 기(期) 보다 삼림에 비해 초지의 분포역이 더욱 넓어졌으며 이 시기의 삼림식생은 침활혼합림이지만 우점 수종에 있어 차이가 있다. YJ-II 기(期)(약 14,650-14,100yrB.P.)는 만빙기에 대비되며 당시의 식생은 YJ-Ib기(期)에 비해 삼림보다 초지의 분포역이 더욱 넓어졌으며 이 시기의 삼림식생은 침엽수림이다. (2) YJ-I 기(期)와 YJ-II 기(期)는 모두 만빙기 후기(약 12,000-10,000yrB.P.)~홀로세 초기(10,000-8,500yrB.P.)에 비해 상대적으로 한랭 건조했다, 그리고 YJ-II 기(期)가 YJ-I 기(期) 보다 상대적으로 한랭했으며, YJ-Ib 기(期)가 YJ-Ia 기(期)에 비해 약간 더 습윤했다.

• 한국산림과학회지
• /
• 제98권2호
• /
• pp.197-202
• /
• 2009

We studied bird communities among in rice field (46 plots), short grallland (47plot), and tall grass mixed shrub (21 plots) during dry season, January 2007 in Boeung Prek Lapouv (BPL) Important Bird Area, Mekong Delta, Cambodia using the point-count method. Water depth, vegetation height and shrub density were significantly different among the three study areas. We recorded, 60 bird species, of which 13 differed significantly among habitats. Landbirds such as Grey-breasted Prinia (Prinia hodgsonii) and Oliver-black Sunbird (Nectarinia jugularis) were much more abundant (P<0.0001) in the tall grass mixed shrub, whereas the Sarus Crane (Grus antigone), herons and egrets were more abundant in the short grass (P<0.05). Bird species richness and species abundances were not significantly different among habitats. Bird species diversity (H') was higher in grasslands than in rice fields. Mosaic habitat matrix, such as rice field, short grass, and tall grass mixed shrub, should be maintained for the extend and quality of wetlands, and the prevailing human-land use patterns, appear adequate and conductive for waterbirds in the Mekong Delta, Cambodia.

• The Korean Journal of Ecology
• /
• 제10권3호
• /
• pp.139-149
• /
• 1987

Mathematical models of the litter accumulation, decay and turnover in the grassland and forest ecosystems of equilibrium state of the annual litter production were established to analyse the decay rates of organic and inorganic constituents of the litter. Those models were validated by an application to a Phragmites longivalvis grassland in a delta of the River Nakdong. The decay constants of cold-water-soluble fractions, other carbohydrates, hot-water-soluble fractions, cellulose, crude fat, lignin and crude protein in the litter were 0.730, 0.583, 0.555, 0.505, 0.479, 0.331 and 0.310 respectively. The amount of mineral nutrients such as N. P. K. Ca and Mg returned annually to the soil were estimated to 7.09, 1.34, 2.36, 4.37 and 0.79g/m2 respectively.