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1.
对陕西省耀县山地不同海拔高度三个酿酒葡萄园0 ̄60cm土层土壤的养分及葡萄生长发育进行了研究。结果表明:各葡萄园土壤pH均在8.0左右,属石灰性土壤;土壤有机质和N、P、K等大量元素含量偏低,各种微量元素除了有效B含量很低以外,其它元素含量均丰富。植株生长量以海拔最低的葡萄园大于其它两地。果实糖酸比随海拔升高而降低,总酚和单宁含量以海拔居中处的最高。  相似文献   
2.
山地酿酒葡萄园土壤理化性质分析   总被引:6,自引:0,他引:6  
侍朋宝  陈海菊  张振文 《土壤》2009,41(3):495-499
对陕西省渭北高原山地3个不同海拔高度酿酒葡萄园0 ~ 60 cm土层土壤的理化性质进行了研究.结果表明:各葡萄园土壤pH均在8.0左右,属碱性土壤;土壤有机质和N、P、K等大量元素含量偏低,各种微量元素除了B含量很低以外,其他元素均含量丰富;各葡萄园土壤理化性质差异很大,从整体上看海拔最低点的最好.土壤养分中速效N、P、K含量与黏粒(<0.002 mm)含量之间呈显著的正相关,与粉粒(0.002 ~ 0.02 mm)含量之间呈显著的负相关.  相似文献   
3.
差高机构对微型履带山地拖拉机稳定性的影响   总被引:1,自引:0,他引:1  
为使微型履带山地拖拉机更好地适应丘陵、山地等地带作业,在现有履带拖拉机的基础上,对其行走系统进行了改进,增加了液压差高机构。根据差高机构的工作原理,运用矢量矩阵理论,建立了差高机构工作时整机质心位置变化的数学模型,并进一步给出了在坡道行驶时允许的最大坡度角。实例分析表明,差高机构使微型履带山地拖拉机纵向稳定性有所降低,但可提高其横向稳定性。  相似文献   
4.
本文在实地考察和试验研究的基础上,对江西清江种草养畜试验站的自然植被资源特点,尤其是草本植物资源及饲用价值,作了综合的分类描述和评价,可供野生试验的优选、驯化培育和天然草坡的改良及合理利用参考。  相似文献   
5.
山地土壤养分及其对酿酒葡萄生长发育的影响   总被引:7,自引:0,他引:7  
对陕西省耀县山地不同海拔高度三个酿酒葡萄园0~60cm土层土壤的养分及葡萄生长发育进行了研究。结果表明:各葡萄园土壤pH均在8.0左右,属石灰性土壤;土壤有机质和N、P、K等大量元素含量偏低,各种微量元素除了有效B含量很低以外,其它元素含量均丰富。植株生长量以海拔最低的葡萄园大于其它两地。果实糖酸比随海拔升高而降低,总酚和单宁含量以海拔居中处的最高。  相似文献   
6.
This study examines transforming real estate value of urban hillside for residential developments, drawing on two-fold panel analyses: a random-effect panel modeling and a growth-curve panel modeling, in Seoul, South Korea from 1990 to 2015. The results reveal the reduced gap between the land values in hillside and low-lying residential sites as moving toward 2015, evidenced by the rapidly growing rate of increase of land value in the former, whereby the parabolic curvature of the land value trajectory increased from 0.00152 to 0.00156, compared to that of the latter, whereby the equivalent to that decreased from 0.00224 to 0.00214. The results also suggest that the negative effect of higher elevation has decreased to approximately zero (−0.625% per 10-m increment) and projected to turn positive, in hillside residential sites, while the equivalent to that in the low-lying residential sites has been exacerbated (−3.786% per 10-m increment). By helping the understanding of the past, current and future hillside housing development—how the hillside sites have been and will be reevaluated by passage of time, this study will provide practical lessons in planning urban housing and natural amenity resources.  相似文献   
7.
通过在南安市丘陵旱地三种不同类型土壤上布置"3417"设计的平衡施肥田间肥料试验,验证NPK肥的施用效果,建立甘薯产量和施肥利润与N、P、K施用量的数学模型,得出在该条件下的甘薯适宜施肥量和比例。结果表明,甘薯施用NPK肥料均获得一定幅度的增产增值效果。获得最高产量的施肥量为154 3~173 6kg/hm2N,44 4~75 3kg/hm2P2O5,193 1~245 3kg/hm2K2O,N P2O5 K2O=1 0 26~0 43 1 24~1 41;最佳经济施肥量为140 0~162 0kg/hm2N,40 8~67 0kg/hm2P2O5,199 8~227 3kg/hm2K2O,N P2O5 K2O=1 0 25~0 41 1 23~1 64。低产田土壤适当增施N肥,P、K比例可以低些,中高产田土壤P、K比例要高些。  相似文献   
8.
臭椿直播造林成活率初探   总被引:3,自引:0,他引:3  
本文通过对不同坡向、不同覆土厚度 ,春秋两季臭椿直播造林的成活率进行了对比调查 ,结果表明 :秋季直播造林 ,阴坡比阳坡、半阴坡成活率高。覆土 4 比覆土 2 、 6 的效果好。春季直播造林 ,阴坡比阳坡、半阴坡成活率高 ,覆土 6 比覆土 2 、 4 的成活率高。春、秋两季直播造林相比 ,秋季比春季成活率高。  相似文献   
9.
 In Kemang, a mountain village in West Java, Indonesia, the local people call the hillsides pasir, a term which includes both privately owned hillside land or nationally owned forest land. It is apparent that the national forest lands function as a social safety net, serving as land where the middle-class and the poor can conduct “informal” cultivation, through temporary agreements with the state forestry corporation, or even “illegal” cultivation without permission. In this study, the households cultivating on national forest lands were identified as: (1) having most household members living together; (2) having a relatively young head person; (3) cultivating a small area of rice field; (4) having participated in the former perhutanan sosial system; (5) being dependent on the income from hillside land; (6) taking advantage of the rare opportunities for off-farm income; and (7) having a low total income. Meanwhile, the talun-huma system is dominant on privately owned hillside land, where a part of the talun, or tree garden, is cleared for use as a swidden on a 30-year rotation. In such cases, the land functions as a safety net only for the limited number of people who are permitted access to the land. The function of the privately owned hillside land, through the mutual-aid system, should not be overestimated; it is probably less important than national forest land in terms of income redistribution. It is recommended that the government of Indonesia consider the possibility of formally ensuring the long-term rights of local people to utilize the national forest lands in Java. Received: April 6, 2001 / Accepted: October 24, 2002 Acknowledgments This paper is in part a result of the research activities of the Core University Program in Applied Bioscience between the University of Tokyo and Bogor Agricultural University, sponsored by the Japan Society for the Promotion of Science (JSPS). The authors would like to express their thanks to Prof. Sumiaki Iwamoto, the University of Tokyo, for his kind help. Correspondence to:M. Inoue  相似文献   
10.
本文对贵州省封山育林发展状况进行了回顾,在深入分析当前封山育林工作存在问题和面临困难的基础上,提出了改进和完善贵州省封山育林技术规定的思考建议。  相似文献   
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