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1.
马铃薯作物的抗逆性较强,相较同类蔬菜,其需水少,喜光,可抵抗多种病毒,田间管理容易,市场价格稳定。目前,干旱区马铃薯产业发展初具规模,但传统发展过程无法避免一些问题,阻碍了马铃薯产业的可持续发展。为了保证马铃薯栽培品质,推广产业化生产,实现马铃薯规模化发展,应系统规划和研究马铃薯产业,以提高马铃薯产业发展水平。通过分析马铃薯栽培技术,提升单产水平,改善品质,获得较好的社会经济效益,实现农业可持续发展。 相似文献
2.
花椒是我国常见的经济树种。本文从建园规划、苗木选择、栽植管理、抚育管理、防冻管理及主要病虫害防治等方面概述了浅山干旱地区有机花椒丰产栽培技术及病虫害防治措施,对有机花椒在浅山干旱地区的推广和规模化栽植具有重要的指导意义。 相似文献
3.
为了探索适合在北方干旱地区造林中大面积推广应用的土壤覆盖措施,提高人工造林的成活率,开展了不同土壤覆盖措施对侧柏林间土壤含水量及造林成活率的影响试验,结果表明:土中覆草的处理蓄水能力更强,明显促进侧柏苗木生长,提高苗木的成活率。我国北方干旱地区应用土中覆草技术可明显提高造林成效。 相似文献
4.
Land surface temperature retrieval for arid regions based on Landsat-8 TIRS data:a case study in Shihezi,Northwest China 总被引:1,自引:0,他引:1
Lei YANG ;YunGang CAO ;XiaoHua ZHU ;ShengHe ZENG ;GuoJiang YANG ;JiangYong HE ;XiuChun YANG 《干旱区科学》2014,(6):704-716
Scientific interest in geophysical information about land surface temperature (LST) is ever increasing, as such information provides a base for a large number of applications, including environmental and agricultural monitoring. Therefore, the research of LST retrieval has become a hot topic. Recent availability of Landsat-8 satel- lite imagery provides a new data source for LST retrieval. Hence, exploring an adaptive method with reliable ac- curacy seems to be essential. In this study, basing on features of Landsat-8 TIRS thermal infrared channels, we re-calculated parameters in the atmospheric transmittance empirical models of the existing split-window algorithm, and estimated the ground emissivity with the help of the land cover classification map of the study area. Further- more, a split-window algorithm was rebuilt by virtual of the estimation model of the updated atmospheric transmit- tance and the ground emissivity, and then a remote sensing retrieval for the LST of Shihezi city in Xinjiang Uygur autonomous region of Northwest China was conducted on the basis of this modified algorithm. Finally, precision validation of the new model was implemented by using the MODIS LST products. The results showed that the LST retrieval from Landsat-8 TIRS data based on our algorithm has a higher credibility, and the retrieved LST is more consistent with the MODIS LST products. This indicated that the modified algorithm is suitable for retrieving LST with competitive accuracy. With higher resolutions, Landsat-8 TIRS data may provide more accurate observation for LST retrieval. 相似文献
5.
QianBing ZHANG Ling YANG ZhenZhu XU YaLi ZHANG HongHai LUO Jin WANG WangFeng ZHANG 《干旱区科学》2014,(4):468-477
Changes in both soil organic C storage and soil respiration in farmland ecosystems may affect atmospheric CO2 concentration and global C cycle. The objective of this field experiment was to study the effects of three crop field management practices on soil CO2 emission and C balance in a cotton field in an arid region of Northwest China. The three management practices were irrigation methods(drip and flood), stubble managements(stubble-incorporated and stubble-removed) and fertilizer amendments(no fertilizer(CK), chicken manure(OM), inorganic N, P and K fertilizer(NPK), and inorganic fertilizer plus chicken manure(NPK+OM)). The results showed that within the C pool range, soil CO2 emission during the whole growing season was higher in the drip irrigation treatment than in the corresponding flood irrigation treatment, while soil organic C concentration was larger in the flood irrigation treatment than in the corresponding drip irrigation treatment. Furthermore, soil CO2 emission and organic C concentration were all higher in the stubble-incorporated treatment than in the corresponding stubble-removed treatment, and larger in the NPK+OM treatment than in the other three fertilizer amendments within the C pool range. The combination of flood irrigation, stubble incorporation and application of either NPK+OM or OM increased soil organic C concentration in the 0-60 cm soil depth. Calculation of net ecosystem productivity(NEP) under different management practices indicated that the combination of drip irrigation, stubble incorporation and NPK+OM increased the size of the C pool most, followed by the combination of drip irrigation, stubble incorporation and NPK. In conclusion, management practices have significant impacts on soil CO2 emission, organic C concentration and C balance in cotton fields. Consequently, appropriate management practices, such as the combination of drip irrigation, stubble incorporation, and either NPK+OM or NPK could increase soil C storage in cotton fie 相似文献
6.
为了筛选适合青海东部干旱地区高产饲用玉米品种,采用单因素随机排列,比较了6个饲用玉米品种生产性能和种植效益。结果表明:豫青贮23株高达288.62 cm,显著高于其他品种;豫玉22鲜草平均产量13.57×10^(4)kg/hm^(2),与豫青贮23和甘玉23平均产量间差异不显著;豫玉22盈利达1.60×104元/hm^(2),较豫青贮23和甘玉23分别提高16.79%和18.52%。从综合表现来看,豫玉22、豫青贮23和甘玉233个饲用玉米品种在青海东部干旱地区具有高产性能和较高的经济效益,值得大力推广应用。 相似文献
7.
<正> 一、草种选择1.根据气候特点选择品种。不同品种的牧草适应不同的气候条件和区域范围。寒冷地区可选择种植耐寒的紫花苜蓿、聚合草、鲁梅克斯 K-1杂交酸模、草木樨、冬牧一70黑麦、无芒雀麦、串叶松香草、沙打旺等;干旱地区可种植耐旱的紫花苜蓿、苏丹草、沙打旺、籽粒苋、鲁梅克斯 K-1杂交酸模、羊草、无芒雀麦、披碱草等;炎热地区可种植串叶松香草、苏丹草、苦荬菜等,但不宜种植无芒雀麦、披碱草、白三叶、红三叶、聚合草等;温暖湿润的地区可种植黑麦草、苏丹草、饲用玉米、白三叶、红三叶、串叶松香草、苦荬菜、聚合草、象草等。2.根据土壤类型选择品种。中性偏碱土壤适宜种植耐碱性强的品种,如紫花苜蓿、沙打旺等;中性偏酸土壤适宜耐酸性强的品种,如红三叶、白三叶等;盐碱地只适宜种植耐盐碱的品种,如沙打旺、黑麦草、籽粒苋、羊草、 相似文献
8.
9.
"张杂谷"是张家口市农科院谷子研究所所长赵治海用近30年培育出来的,是我国继培育杂交水稻之后,又一项具有自主知识产权的农业技术。据测算张杂谷最高亩产可达810kg,米质优良,适口性好,而且抗旱性能高,在广大的北方干旱地区,包括沟壑纵横的丘陵、山区的贫瘠土地上,依靠自然降水完全可以稳产高产。 相似文献
10.