• Asian-Australasian Journal of Animal Sciences
• /
• 제22권9호
• /
• pp.1256-1266
• /
• 2009

Effects of particle size and physical effective fibre (peNDF) of rice straw in diets on chewing activities, feed intake, flow, site and extent of digestion and rumen fermentation in goats were investigated. A 4${\times}$4 Latin square design was employed using 4 mature Liuyang black goats fitted with permanent ruminal, duodenal, and terminal ileal fistulae. During each of the 4 periods, goats were offered 1 of 4 diets that were similar in nutritional content but varied in particle sizes and peNDF through alteration of the theoretical cut length of rice straw (10, 20, 40, and 80 mm, respectively). Dietary peNDF contents were determined using a sieve for particle separation above 8 mm, and were 17.4, 20.9, 22.5 and 25.4%, respectively. Results showed that increasing the particle size and peNDF significantly (p<0.05) increased the time spent on rumination and chewing activities, duodenal starch digestibility and ruminal pH, and decreased ruminal starch digestibility and $NH_{3}$-N concentration. Intake and total tract digestibility of nutrients (i.e. dry matter, organic matter, and starch) and ruminal fermentation were not affected by the dietary particle size and peNDF. Increased particle size and peNDF did not affect ruminal fibre digestibility, but had a great impact on the intestinal and total tract fibre digestibility. The study suggested that rice straw particle size or dietary peNDF was the important influential factor for chewing activity, intestinal fibre and starch digestibility, and ruminal pH, but had minimal impact on feed intake, duodenal and ileal flow, ruminal and total tract digestibility, and ruminal fermentation.

• Asian-Australasian Journal of Animal Sciences
• /
• 제23권8호
• /
• pp.1022-1027
• /
• 2010

Effects of increasing dietary rice straw on chewing activity, ruminal fermentation, and fibrolytic enzyme activity in growing goats were investigated in a $4{\times}4$ Latin Square experiment. The goats were offered four diets with an increasing proportion of rice straw (i.e. 0.05, 0.10, 0.15 and 0.20, respectively, on dry matter basis). Increasing level of rice straw increased ($P_{linear\;effect}$ <0.05) the time spent on eating, ruminating, and chewing. The ruminal pH and acetate: propionate ratio were increased ($P_{linear\;effect}$ <0.05), while the $NH_3$-N concentration was decreased ($P_{linear\;effect}$ <0.01). Increasing level of rice straw in the diet increased ($P_{linear\;effect}{\leq}0.01$) molar proportion of acetate and isovalerate, and decreased ($P_{linear\;effect}$ <0.01) molar proportion of propionate. The CMCase, xylanase and cellobiase activities in the rumen were decreased ($P_{linear\;effect}$ <0.05) with increasing level of dietary rice straw, whereas the avicelase activity was increased ($P_{linear\;effect}$ <0.01). In summary, increased level of rice straw elevated the dietary neutral detergent fibre (NDF) content in the diet and had a great impact on chewing activity and ruminal fermentation.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2005년도 국제학술회의
• /
• pp.22-46
• /
• 2005

Spatial and timely information on crop and filed conditions is one of the most important basics for rational and efficient planning and management in agriculture. Remote sensing, GIS, and modeling are powerful tools for such applications. This paper presents an overview of the state of the art in remote sensing of crop and field conditions with some case studies. It is also shown that a synergistic linkage between process-based models and remote sensing signatures enables us to estimate the multiple crop/ecosystem variables at a dynamic mode. Remotely sensed information can greatly reduce the uncertainty of simulation models by compensating for insufficient availability of data or parameters. This synergistic approach allows the effective use of infrequent and multi-source remote sensing data for estimating important ecosystem variables such as biomass growth and ecosystem $CO_2$ flux. This paper also shows a geo-spatial information system that enables us to integrate, search, extract, process, transform, and calculate any part of the data based on ID#, attributes, and/or by river-basin boundary, administrative boundary, or boundaries of arbitrary shape/size all over Japan. A case study using the system demonstrates that the nitrogen load from fertilizer was closely related to nitrate concentration of groundwater. The combined use of remote sensing, GIS and modeling would have great potential for various agro-ecosystem applications.

• 한국환경농학회지
• /
• 제28권4호
• /
• pp.356-364
• /
• 2009

In 2006 and 2007, there was a big outbreak of the Ussur Brown Katydid, Paratlanticus ussurriensis in the central part of Korea attacking some orchard trees. Until 2000, the katydid had not been regarded as an agricultural pest because they were distributed widely in Korea with low population density and their habitats were confined mainly to hillsides of forested areas. The fact that katydid attacked orchard trees with a higher population density seemed to be related to a change in feeding environment. And the shift of their habitats from oak woodlands to commercial orchards was thought to be related to the nutritional contents of their feed. In an attempt to understand these relationships, we conducted an ecological study of the affected areas. When the katydids changed their habitats in early May of 2008 and 2009, they shifted their host plants from oak trees to peach trees. The habitat shift was closely related to the nitrogen (N) content of the host plant leaves. When katydid moved to the hillside adjacent to orchard farm, N content of oak tree leaves decreased dramatically from 5.3% to 2.2%. At that time N content of peach tree leaves were higher than the 2.2% of oak leaves, showing 3.5~5.0%. This range of N content of peach tree leaves has been consistent until late June. And feed preference analysis carried out in the laboratory showed that katydid prefered peach tree leaves to peach fruit to oak tree leaves.

• 한국응용곤충학회지
• /
• 제48권4호
• /
• pp.423-429
• /
• 2009

충북 영동지역에서 대발생한 갈색여치의 서식지 변화 및 배자후발육의 특징에 관해서 2007년에서 2009년까지 3년간 조사하였다. 갈색여치의 월동알은 3월말에서 4월초까지 약 2주 동안 야산에서 부화하였으며, 이 기간의 지온은 $7{\sim}14^{\circ}C$로 측정되었다. 부화한 약충은 야산에 서식하며 참나무류의 잎을 가해하였으나 5월 초순경에 3-4령이 되면서 과수원으로 서식처를 이동하였다. 이 시기는 비탄리 일대 과수원 복숭아잎이 개엽하는 시기와 일치하였다. 갈색여치는 복숭아 잎을 가해하면서 성충까지 발육하였고 6월 하순경에 다시 인근 야산으로 이동하였다. 갈색여치는 부화 후 성충이 되기까지 평균 7회 탈피를 하며, $25^{\circ}C$에서 그 기간은 평균 49.2일이었다. 야외에서 채집한 암컷 성충은 평균 26.2 mm의 긴 산란관을 가지며 앞가슴등판 및 뒷다리 퇴절의 크기가 수컷보다 컷다.

• 한국환경농학회지
• /
• 제28권3호
• /
• pp.238-242
• /
• 2009

우분의 분해에 있어 소똥구리와 지렁이를 함께 처리한 구에서 단독으로 소똥구리와 지렁이를 처리한 것 보다 분해율이 높았고, 지렁이와 소똥구리가 우분 분해 활동을 한 다음에 식물체를 파종했을 때 식물체 생장은 비료를 처리한 것과 동일한 효과가 인정되었다. 우분 함수율 78%까지는 소똥구리에 의해 분해 활동이 일어나며, 30%까지는 지렁이에 의해, 30% 이하에서는 두 동물군 모두 분해 활동을 하지 않았다. 소똥구리와 지렁이에 의해 운반된 우분은 초기 우분의 약 72%이며, 이중 10.2%는 소똥구리의 brood ball 형성에 이용되었다. 지렁이의 활동이 소똥구리의 brood ball 형성에 저해요인이 되지 않았고, 소똥구리의 활동 또한 지렁이의 생육에 영향을 미치지 않아 지렁이와 소똥구리는 우분에서 공간적 분포를 같이 하면서 먹이 경쟁을 하기 보다는 상호보완적인 작용을 하는 것으로 밝혀졌다.

• 한국농림기상학회:학술대회논문집
• /
• 한국농림기상학회 2011년도 학술발표회
• /
• pp.36-36
• /
• 2011

• 한국농림기상학회:학술대회논문집
• /
• 한국농림기상학회 2015년도 하계 학술발표논문집
• /
• pp.59-63
• /
• 2015

• 한국응용곤충학회지
• /
• 제48권2호
• /
• pp.221-227
• /
• 2009

갈색여치 알의 휴면타파에 대한 온도의 영향을 조사하기 위하여 실내 및 야외의 다양한 온도조건에서 배자발달 및 부화율을 측정하였다. 갈색여치 휴면알을 $25^{\circ}C$에서 계속 사육할 경우 부화하지 않았으며 1회 저온처리($5^{\circ}C$ 또는 $10^{\circ}C$에서 30, 45, 60일간)한 후 $25^{\circ}C$에서 사육해도 부화하지 않았다. 또한, $5^{\circ}C$에서 같은 기간 동안 2회 저온처리를 한 경우에도 부화하지 않았다. 그러나 $10^{\circ}C$에서 2회 반복하여 저온처리를 했을 때에 3.6${\sim}$26.7%의 알이 부화하였다. 1회 저온처리 후 $25^{\circ}C$에서 부화하지 않은 알의 무게를 측정한 결과 $5^{\circ}C$에서 저온처리한 알들은 변하지 않았으나 $10^{\circ}C$의 경우에는 1.5배 증가했다. 90일 된 알을 2007년 9월에 산간지역 3곳의 땅속에 묻은 후에 월동후 부화율을 관찰한 결과, 충북 영동 회포리, 비탄리 및 경북 화산리에서 1회 월동알의 부화율은 11.3, 3.5, 4.1%였지만 2회 월동알은 25.1, 21.6, 0.4%였다. 부화는 3월 중순부터 4월 중순 사이이지만 남쪽에서 약간 일찍 부화하였다. 이 시기의 토양온도는 8${\sim}$$12^{\circ}C$로 나타났다. 본 연구결과 갈색여치 휴면알은 반복적인 저온기간의 영향이 크며 야외에서는 1회 또는 2회의 월동기간이 필요한 것으로 판단된다.

• The Korean Journal of Ecology
• /
• 제27권1호
• /
• pp.21-26
• /
• 2004

Understanding farmer household and community management of crop diversity is necessary in order to effectively strengthen the local plant genetic resources management system in Vietnam, Assessment and management for distribution of farmer's cultivars of rice, taro and tropical tree species were conducted in four different agro-ecological zones in Vietnam using participatory approaches, focus surveys, diversity fairs, agro-morphological field trials, isozyme analysis to understand why Vietnamese farmers grow diverse types of these crop cultivars, when and where these crops cultivars are grown and how farmers maintain and use them. Results showed significant differences in the extent, distribution and use pattern crop cultivars diversity in contrasting environments and between community farmer households. Seed system is an important role in the access and use of diversity in eco-geographical regions.