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石漠化生态恢复过程中土壤磷含量的比较研究(英文) 总被引:11,自引:2,他引:9
[Objective] The research aimed to study change law of phosphorus content of soil in karst rocky desertification region(KRD) during eco-restoration process such as Northwest Guangxi Province.[Method] The soil samples were collected from typical KRD in Pingguo County and Yizhou City.The determining quotas of different soil samples such as soil total phosphorus content and available phosphorus content were detected,in addition the soil total phosphorus content,available phosphorus content, urease activity, catalase activity and organic matter content in different soil samples were analyzed comparatively.[Result] Aspect,vegetation type and recovery time generated obviously influences on phosphorus contents in different soil samples.The concrete influence order was listed as follow: phosphorus content in soil of south slope was higher than that in soil of north slope;phosphorus content in soil where Zenia insignis Chun was planted was higher than that in soil of closed forest and that of soil where Dendrocalamus minor Var. amoen was planted,additionally,phosphorus increased with recovery time. Urease activity could be used as a monitoring index of soil fertility because it is related to the change of phosphorus content.[Conclusion] The soil of karst rocky desertification region in Northwest Guangxi Province could be recovered gradually if excessive human disturbance was stopped.If proper natural method of recovery promoted by human was taken,the recovery would reach a better result. 相似文献
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采用文献调查和实地考察相结合的方法,对桂西北岩溶地区古树附生或寄生维管束植物进行调查研究,了解喀斯特地区古树栖居的高等植物的常见种类、分布特点、传播方式及其对古树的影响,探讨岩溶地区古树保护的策略以及珍稀物种生物学保护的有关措施。调查结果发现,桂西北岩溶地区古树寄居植物共有40科59属68种,其中寄生植物4种,附生植物64种。寄居植物的分布与古树的年龄、树种及生境有一定的关系,其繁殖体主要通过风媒或鸟媒等途径传播,并且对生活环境有良好的适应性。寄居植物以草本植物种类居多,蕨类、兰科植物和寄生植物种群数量最大。寄居植物(寄生植物除外)与宿主(古树)之间主要表现为互利共生关系,一般不会对古树造成严重影响。为保护古树及寄居的珍稀物种,笔者提出了五点有关建议和措施。 相似文献
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正当前,农业产业管理技术正由粗放型向集约型转变,增长方式正由追求数量向追求质量过渡。合理的进行农业产业管理,将有效解决"结构、品种、质量、效益"问题,提高农产品市场竞争能力。总的来说,新时期农作物栽培技术的管理,将成为现阶段农业科技发展面临的首要任务。1农作物栽培技术管理的原则1.1生态生理机制为基础作物栽培技术的确定,需综合考虑光合作用、生理特点、生态因子调控等,以超高产的生态生理机制为基础,确 相似文献
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