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树干注射几种有机磷农药后果实中原药残留研究 总被引：1，自引：0，他引：1
以梨和苹果为材料,树干注射４种有机磷农药后第１３ｄ分析,果实中原药残留分别为：氧化乐果１．９、２．４ｍｇ／ｋｇ,久效磷１．３、１．８ｍｇ／ｋｇ,水胺硫磷１．８、３．０ｍｇ／ｋｇ,甲胺磷１.２、０．８ｍｇ／ｋｇ;第２５ｄ果实中原药残留仅在苹果中测到水胺硫磷０．００１×１０－６～０．００５×１０－６,其余３种均未检测出。根据美国、日本的上述４种农药在苹果、梨中最高残留限量：甲胺磷、久效磷、水胺硫磷均为１．０ｍｇ／ｋｇ,氧化乐果２．０ｍｇ／ｋｇ的要求,建议安全间隔期为３０ｄ。 相似文献
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采用完全随机排列的方法并对９个剑麻品种的生物量，纤维率，抗寒性等综合指标进行分析评定，同时以Ｈ．１１６４８为主要试验对象验证生产栽培技术。结果表明（１）Ｈ．１１６４８生长表现最佳，其叶宽较其它参试品种高０．４－１．７ｃｍ，纤维率４．６５％较其它品种高１．９３％－３．４８％，仅比东７４低０．１５％。（２）栽植剑麻合理的整地方式为宽窄行，大行距２．０－３．５ｍ，小行距１．０－２．０ｍ，适宜密度为４５５ 相似文献
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提高杉木种子园种子产量及品质技术措施的研究 总被引：8，自引：0，他引：8
对湖南省东安县杉木无性系种子园施肥试验的结果表明：３、６、８月中旬每次每株各施尿素０．４ｋｇ、过磷酸钙０．３ｋｇ、氯化钾０．２ｋｇ为球花产量最高的施肥方案；施肥对当年的种子播种品质有影响，但不大；种子园大片母树不挂果的原因是土壤和树体中锰含量过高而树体中的硼元素缺乏，对此提出对土壤施石灰和对母树针叶喷Ｂ肥的改良措施；３—８月是杉木种子园施Ｎ、Ｐ．Ｋ肥最适宜时期；确定８月是杉木种子园母树营养诊断进行针叶分析的最佳采样时期，并制定出杉木种子园母树的针叶中全Ｎ含量为０．８％、全Ｐ含量为０．１２％、全Ｋ含量为０．７％是其临界值；针叶全Ｎ含量０．８—１．２％、全Ｋ含量０．７－０．９％是其最适浓度范围；中耕松土对种子园种子产量影响不明显。 相似文献
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内蒙古磴口河套地区４ａ灌溉试验表明：（１）采用目前生产上的１５０００－２２５００ｍ＾３／（ｈｍ＾２．ａ）灌溉量，使土壤表层的含盐量由灌溉前的０．５ｇ／ｋｇ上升到１．０ｇ／ｋｇ以上。（２）按合理灌水定额公式计算，年灌溉量以７５００ｍ＾３／ｈｍ＾２为宜；最佳含水率下限１９．９９％；在灌水期地下水位为１．９７－３．０２ｍ，变幅１ｍ左右（３）年灌水次数应控制在８－１２次。 相似文献
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Growing woody biomass for bioenergy in a tree-based intercropping system in southern Ontario, Canada
Rémi Cardinael Naresh Thevathasan Andrew Gordon Rachelle Clinch Idris Mohammed Derek Sidders 《Agroforestry Systems》2012,86(2):279-286
During the spring of 2006, three willow varieties (SV1, SX67 and 9882-41) were established on marginal land in an agroforestry tree-intercropping arrangement where plots of short rotation willows were planted between rows (spaced 15?m apart) of 21-year-old mixed tree species. As a control, the same varieties were established on an adjacent piece of land without established trees (conventional willow system). This study investigated the magnitude of carbon pools, fine root and leaf biomass inputs and clone yields in both the tree-based intercropping (agroforestry) and conventional monocropping systems. Willow biomass yield was significantly higher in the agroforestry field (4.86?odt?ha?1?y?1) compared to the conventional field (3.02?odt?ha?1?y?1). In both fields, varieties SV1 and SX67 produced higher yields than the variety 9882-41. Willow fine root biomass in the top 20?cm of soil was significantly higher in the intercropping system (3,062?kg?ha?1) than in the conventional system (2,536?kg?ha?1). Differences in fine root biomass between clones were similar to that observed for differences in biomass yield: SV1?>?SX67?>?9882-41. Leaf input was higher in the intercropping system (1,961?kg?ha?1) than in the conventional system (1,673?kg?ha?1). Clonal differences in leaf inputs followed the same trends as those for root biomass and yield: SV1?>?SX67?>?9882-41. Soil organic carbon was significantly higher in the agroforestry field (1.94?%) than in the conventional field (1.82?%). A significant difference in soil organic carbon was found between the three clones: soils under clone 9882-41 had the lowest soil organic carbon at 1.80?%. 相似文献
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多糖是醋栗果实中具有重要生理功能的活性成分。以醋栗果实为原料,以醋栗多糖得率为指标,采用响应面法优化醋栗多糖的制备工艺。结果表明,在4种影响因素中,提取温度与提取时间的交互作用对醋栗多糖得率的影响最为显著;提取时间44min,超声功率100W,提取温度57℃,水料比为29∶1,在该条件下醋栗多糖得率为15.79%。该结果为醋栗果实多糖提取工艺研究及功能性成分的开发提供一定的理论基础。 相似文献
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川中丘陵地玉米避灾减灾栽培技术研究 总被引：1，自引：0，他引：1
以川中丘陵的典型地三台为基点,从影响玉米产量的主导因子——干旱着手,对品种、播期、密度、肥料投入四因素进行不同生态区品种同田展示、播期试验、三元二次正交回归旋转试验、三元二次正交回归通用设计试验研究,结果经计算机分析,将玉米栽培技术组装配套。得出,根据不同种植地所处的生态区域和台位分布选择相应的品种;谷雨节前后播种,叶面积系数与单株生产力协调一致达最佳,玉米产量最高,既能抗夏旱又能避伏旱;每667平方米种植3500～4000株、施纯氮20公斤以上、施氧化钾9公斤、单产可达500公斤以上;单产600公斤的栽培方案为每667平方米种植4673株、施纯氮26.73公斤、施氧化钾9公斤。 相似文献
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E. M. B. P. Ekanayake Mi Feng Theodore Murindahabi A. H. S. Nissanka G. S. D. G. Patrick 《Small-Scale Forestry》2018,17(2):277-292
Indian gooseberry, one of the most popular medicinal fruit crops in South and Southeast Asia, has become an important source of income for rural forest dwellers in Sri Lanka. However, very little is known about the role of Indian gooseberry in household economies and its contribution to the local and national economies. To address this issue, we conducted a study in Udadumbara Divisional Secretariat, Sri Lanka to estimate the economic contribution of Indian gooseberry to household incomes and to quantify its dependency level among households with different socio-economic characteristics. The data were collected from 117 households through interviews using semi-structured questionnaires. The results show that Indian gooseberry contributes on average 10.1% of the total household income, which is the third largest share after off-farm income (53.1%) and agricultural income (35.1%). The contribution of Indian gooseberry to the household income increases as other sources of income decrease which results in higher contributions for lower income households (16.4%) and lower contributions for higher income households (2.1%). Indian gooseberry income is significantly and negatively correlated with the agricultural land owned by households and water availability for agriculture and is positively correlated with the time spent for collection. Our results also found that if there is access to other sources of income and higher levels of education, the collectors’ dependences on Indian gooseberry are decreased. Moreover, the study found that Indian gooseberry trees are under a threatened and declining due to the reduction of forest cover and inappropriate management system. Therefore, collaborative management system through partnerships among rural community and the Forest Department is suggested. 相似文献
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通过常规理化分析研究鄂尔多斯市东胜区森林公园的土壤质量状况,结果表明,森林公园土壤容重大,平均为1.50 g/cm3;石砾含量高,除2个黑土样本外,石砾质量分数均大于20%;盐分偏低,Ec值在0.1~0.2 m S/cm;p H值较高,在8.8~9.1,均为强碱性土壤;土壤有机质、碱解氮、有效磷含量均较低,分别在0.6~10.5 g/kg,3.9~43.2 mg/kg,2.6~6.7 mg/kg,且上层土壤含量大于下层土壤;有效钾含量在26.4~87.2 mg/kg,多数处于较低水平,土壤上、下层含量差异无明显规律。总体上说,森林公园土壤质量较差。根据森林公园土壤质量状况,文中提出了加强鄂尔多斯市东胜区绿地土壤科学管理的措施和建议。 相似文献
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本文对3个优良无花果品种在威远的引种适应情况进行了分析.通过对布兰瑞克、玛斯义陶芬和金傲芬的引种试验,将各品种的物候期、生长习性、果实性状以及果实产量与本地无花果品种进行比较分析.结果表明,3个无花果优良品种均能很好地适应威远的气候及土壤条件.引种无花果品种2003年定植当年单株挂果率均达到100％,次年生长迅速变化幅度最大,增幅主要源于新抽梢果枝的增加.与本地无花果品种比较发现,引进品种无花果果实在风味、平均果长、平均果径及平均果重方面明显优于本地品种,其中布兰瑞克的平均hm2产量最高,10 a生树平均hm2产量为31 500 kg;相同立地条件下,引进品种无花果果树生长水平、平均单株产量以及平均公顷产量均明显高于本地品种.3个无花果优良品种可以引入威远栽培. 相似文献
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集水造林林分水分生产力研究 总被引：13，自引：2，他引：13
集水造林通过增加植树带汇流量改善了林地土壤水分环境 ,从而影响到林分物质生产水平。根据不同集水造林密度对林地土壤水分环境的改善程度与林分物质生产之间的关系 (水分生产力 ) ,以“双优”模式标准 ,可以确定出合理的集水造林密度。供试的 5年生和 1 0年生刺槐林 ,分别以小于 1 0 0 0株·hm-2 和不大于 840株·hm-2 为合理的集水造林密度 ,其林木水分生产力分别达到 6 71 4 4g·kg-1和 1 2 1 6 32g·kg-1,符合“丰产理想株型”模式标准 ;林分水分生产力分别达到 8 4 1 0 3kg·hm-2 ·mm-1和 2 1 6 6 46kg·hm-2 ·mm-1,实现了“最佳群体结构”模式标准。在发展“节水”型林业、提高水分利用效率中 ,这种以水分与林分物质生产的关系为理论依据 ,确定造林密度 ,在理论和实践上是可取的 相似文献
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内蒙古几个沙地土壤理化性状调查研究 总被引：4，自引：0，他引：4
本文对内蒙古科尔沁沙地、浑善达克沙地和库布齐沙漠土壤理化性质进行了调查研究。结果表明：在土壤0～60cm土层范围内,库布齐沙漠土壤容重平均为1．45g／cm^3,科尔沁沙地为1．50g／cm^3。科尔沁沙地各类土壤平均养分含量分别为：全氮0．042％,全磷0．018％,全钾2．706％,速效磷3．274mg／kg,速效钾35．190mg／kg,有机质9．095g／kg,pH值7．5;在库布齐沙漠：全氮0．014％,全磷0．035％,全钾1．808％,速效磷1．353mg／kg,速效钾67．360mg／kg,有机质平均含量为6．216g／kg,pH值为9;在浑善达克沙地：速效磷4．032mg／kg,速效钾67．247mg／kg,有机质含量为7．450g／kg,pH值为7．5。土壤微生物在沙地土壤养分循环过程中具有重要的作用,土壤真菌、放线菌、细菌平均数量在库布齐沙漠分别为：2．4×10^3个／g（土）、1．8×10^5个／g（土）和1．8×10^6个/g（土）;科尔沁沙地分别为：6．6×10^4个／g（土）、3．8×10^5个／g（土）、1．3×10^6个／g（土）。在土壤微生物群落结构中,细菌大约占73．5％-91．9％,放线菌约占7．8％-22．5％,真菌数量最小。土壤有机质含量是影响微生物数量的主要因子,二者间具有良好的线性相关关系。 相似文献