围栏是一种广泛使用的草地管理措施。磷是植物生长发育不可或缺的营养元素,研究围栏管理对土壤磷含量的影响和驱动,对高寒草地生态系统修复和适应性管理具有重要意义。然而,目前缺乏系统的围栏管理对土壤磷含量的影响研究。本文基于Web ...围栏是一种广泛使用的草地管理措施。磷是植物生长发育不可或缺的营养元素,研究围栏管理对土壤磷含量的影响和驱动,对高寒草地生态系统修复和适应性管理具有重要意义。然而,目前缺乏系统的围栏管理对土壤磷含量的影响研究。本文基于Web of Science核心数据库和中国知网(CNKI)检索平台,筛选了101篇文献开展Meta分析,探究不同高寒草地土壤全磷(STP)与速效磷(SAP)含量对围栏管理措施及围栏年限(短期1~4年,中期5~8年和长期9~30年)的响应。结果表明:1)总体而言,围栏显著提升了STP、SAP、全氮(STN)、有机碳(SOC)、速效氮(SAN)和含水量(SM)(P<0.001),却导致了pH和容重显著降低(P<0.01)。2)围栏对高寒草原STP和SAP的正效应显著高于其对高寒草甸磷含量的影响(P<0.001)。3)针对围栏年限,发现中长期围栏对草甸STP具有极显著的正效应(P<0.001),同时短期围栏能够极显著促进草原STP(P<0.001),中长期围栏则会导致草原STP降低;围栏始终有利于提升SAP,且中期围栏对草原SAP的效应最大。4)围栏管理下STP、STN和SOC的效应值存在协同变化规律,且围栏对STP的效应值随气温的升高而显著增加,但土壤pH的降低促进了围栏对STP的效应值的显著增加。此外,围栏对STN与SAP的效应值呈显著正相关关系。本研究揭示了合理的围栏管理有利于提高高寒草地生态系统的土壤磷含量,结果可为高寒草地管理提供理论参考。展开更多
In this paper we make a close study of the finite analytic method by means of the maximum principles in differential equations and give the proof of the stability and convergence of the finite analytic method.
An analytic method of fractional steps, which is unconditionally L_∞-stable, is proposed for the numerical solution to convection-dominated problems. In this paper the stability and convergence of the analytic soluti...An analytic method of fractional steps, which is unconditionally L_∞-stable, is proposed for the numerical solution to convection-dominated problems. In this paper the stability and convergence of the analytic solution with fractional steps to both linear and nonlinear problems are proved, and its error estimates are presented.展开更多
A fractional-step method of predictor-corrector difference-pseudospectrum with unconditional L2-stability and exponential convergence is presented. The stability and convergence of this method is strictly proved mathe...A fractional-step method of predictor-corrector difference-pseudospectrum with unconditional L2-stability and exponential convergence is presented. The stability and convergence of this method is strictly proved mathematically for a nonlinear convection-dominated flow. The error estimation is given and the superiority of this method is verified by numerical test.展开更多
Animal feces are regionally important resources and biomass energy,with large environmental,economic,and social influences across the alpine pastoral areas.In grassland ecosystems,the decomposition of animal feces can...Animal feces are regionally important resources and biomass energy,with large environmental,economic,and social influences across the alpine pastoral areas.In grassland ecosystems,the decomposition of animal feces can strongly affect carbon and nitrogen cycling indirectly through changes in soil and plant properties.展开更多
文摘围栏是一种广泛使用的草地管理措施。磷是植物生长发育不可或缺的营养元素,研究围栏管理对土壤磷含量的影响和驱动,对高寒草地生态系统修复和适应性管理具有重要意义。然而,目前缺乏系统的围栏管理对土壤磷含量的影响研究。本文基于Web of Science核心数据库和中国知网(CNKI)检索平台,筛选了101篇文献开展Meta分析,探究不同高寒草地土壤全磷(STP)与速效磷(SAP)含量对围栏管理措施及围栏年限(短期1~4年,中期5~8年和长期9~30年)的响应。结果表明:1)总体而言,围栏显著提升了STP、SAP、全氮(STN)、有机碳(SOC)、速效氮(SAN)和含水量(SM)(P<0.001),却导致了pH和容重显著降低(P<0.01)。2)围栏对高寒草原STP和SAP的正效应显著高于其对高寒草甸磷含量的影响(P<0.001)。3)针对围栏年限,发现中长期围栏对草甸STP具有极显著的正效应(P<0.001),同时短期围栏能够极显著促进草原STP(P<0.001),中长期围栏则会导致草原STP降低;围栏始终有利于提升SAP,且中期围栏对草原SAP的效应最大。4)围栏管理下STP、STN和SOC的效应值存在协同变化规律,且围栏对STP的效应值随气温的升高而显著增加,但土壤pH的降低促进了围栏对STP的效应值的显著增加。此外,围栏对STN与SAP的效应值呈显著正相关关系。本研究揭示了合理的围栏管理有利于提高高寒草地生态系统的土壤磷含量,结果可为高寒草地管理提供理论参考。
文摘In this paper we make a close study of the finite analytic method by means of the maximum principles in differential equations and give the proof of the stability and convergence of the finite analytic method.
文摘An analytic method of fractional steps, which is unconditionally L_∞-stable, is proposed for the numerical solution to convection-dominated problems. In this paper the stability and convergence of the analytic solution with fractional steps to both linear and nonlinear problems are proved, and its error estimates are presented.
基金the National Natural Science Foundation of China
文摘A fractional-step method of predictor-corrector difference-pseudospectrum with unconditional L2-stability and exponential convergence is presented. The stability and convergence of this method is strictly proved mathematically for a nonlinear convection-dominated flow. The error estimation is given and the superiority of this method is verified by numerical test.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research(2019QZKK0405)the Joint Research Project of Three-River-Resource National Park funded by the Chinese Academy of Sciences+1 种基金Qinghai Provincial People’s Government(LHZX-2020-08)the Public Welfare Project of Qilian Mountain National Park funded by Qilian Mountain Nature Reserve Administration of Qinghai Province(QHXH-2021-07-19-package 2)。
文摘Animal feces are regionally important resources and biomass energy,with large environmental,economic,and social influences across the alpine pastoral areas.In grassland ecosystems,the decomposition of animal feces can strongly affect carbon and nitrogen cycling indirectly through changes in soil and plant properties.
