Results 11 to 20 of about 1,090,864 (151)

丘间低地不同年龄沙柳表层土壤水分与容重的空间变异

open access: yesShuitu Baochi Xuebao, 2007
以毛乌素沙地丘间低地不同年龄(2~4年)沙柳为研究对象,采用地统计学方法对各年龄沙柳表层(0~20cm)土壤水分与容重空间变异进行研究。结果表明:随着年龄的增长,表层土壤水分含量表现出增大的趋势,且各年龄沙柳表层土壤水分含量间表现出一定的差异性(P0.05)。
姚月锋, 蔡体久
doaj   +2 more sources

无定河黄土区降水和产沙的相关性及其时空变异

open access: yesShuitu Baochi Xuebao, 2020
通过泰森多边形加权变差系数法研究了黄河中游无定河流域黄土区降水和侵蚀产沙的空间变异规律,并用线性回归分析探究两者空间变异性的相关性。以黄河主要泥沙来源区之-的无定河流域为例,分析了该流域黄土区1959—2015年水土保持措施综合治理前后降水和侵蚀产沙的时空变异规律,所选用的降水特征为汛期降水(Pflood)和汛期降雨侵蚀力(Rflood),用产沙模数(SSY)表示该流域产沙量的多少。结果表明:(1)在水土流失治理前(1959—1970年),该地区降水特征与产沙模数在时间上的增减变化趋势-致 ...
张萍, 郑明国, 蔡强国, 马小晴
doaj  

科尔沁沙地沙质草场土壤水分对干旱和降雨响应的空间变异性

open access: yesShuitu Baochi Xuebao, 2005
采用地统计学的方法,研究了科尔沁沙地沙质草场土壤含水量对干旱和降雨响应的空间变异规律。结果表明,干旱时沙质草场表层(0~20cm)、亚表层(20~40cm)土壤含水量可很好地拟合成球状模型和指数模型,在1~2.26m,1~6.63m的中等尺度范围内表现出很高的空间自相关性,空间自相关度分别为0.92,0.87.分维数均表现出较弱的空间依赖性.分别为1.99,1.94,两层土壤含水量变异特征差异小,土壤水分的空间变异性强,破碎化程度高。降雨后沙质草场土壤表层 ...
左小安 赵学勇 赵哈林 李玉霖 移小勇 黄刚
doaj   +2 more sources

Human‐Caused Leopard Deaths in Sri Lanka Are Concentrated in Central Highlands' Estate Mosaics: Evidence From 17 Years of Mortality Records 人为因素导致斯里兰卡豹死亡事件集中于中部高地种植园镶嵌景观:来自 17 年死亡记录的证据

open access: yesWildlife Letters, EarlyView.
Human‐caused leopard deaths in Sri Lanka averaged 9.65 ± 4.5 records year−1 over 17 years (2008–2024; n = 164), with records highly clustered in the central highland mosaic ecosystem. Mortality was dominated by adult males and driven primarily by snaring in plantation landscapes, and indicating an increase approximately 0.7–0.8 deaths per year.
Sanjaya Weerakkody   +11 more
wiley   +1 more source

黄灌沙区农田耕层土壤性状空间异质性分析

open access: yesShuitu Baochi Xuebao, 2005
用地统计学的方法,研究了黄灌沙区农田耕作层(030 cm)土壤的有机质、全氮、碱解氮、速效磷、速效钾、pH和电导率的空间变异规律。结果表明,农田耕作层土壤养分的空间异质性主要由随机性因子如土壤耕作措施,包括施肥、灌溉和作物轮作等造成,这与该区农田耕作层土壤是引黄灌溉改良的结果有关。土壤养分含量的变异函数均可很好地拟合成线性模型,块金值和基台值之比(C0/C0 C)均为1,说明随机性因子是导致该区土壤性状空间变异的主要因素,在整个尺度上具有恒定的变异,造成了土壤性状的相对均一。pH的变异函数为指数模型 ...
贾晓红 李新荣 周海燕 樊恒文 赵金龙 李元寿
doaj   +2 more sources

Scaling from microsite to landscape to resolve litter decomposition dynamics in globally extensive drylands

open access: yesFunctional Ecology, EarlyView.
Read the free Plain Language Summary for this article on the Journal blog. Abstract Decomposition is the transformation of dead organic matter into its inorganic constituents. In most biomes, decomposition rates can be accurately predicted with simple mathematical models, but these models have long under‐predicted decomposition in globally extensive ...
Heather L. Throop   +8 more
wiley   +1 more source

关中平原田间土壤含水量的空间变异性

open access: yes, 2020
为了明确田块尺度土壤含水量的空间变异特征,制定合理准确的土壤采样方法,支持田间精准灌溉,分7个日期对陕西省杨凌区曹新庄试验区土壤样品进行采集,利用经典统计学和地统计学方法,分析了0~60 cm不同土层土壤含水量的空间变异特点。结果表明:田块尺度土壤含水量空间分布呈弱变异或中等偏弱变异;土壤含水量在11.7%~20.1%时,其值越低,空间变异性越强。采样间距显著影响土壤含水量空间变异性的计算精度,采样间距设置为东西方向间距27 m和南北方向间距9 m时的土壤含水量变异系数比采样间距设置为东西方向间距9 ...
牛文全, 李国春, 张诗祁
core   +1 more source

Organ‐specific ozone and nitrogen legacies strengthen substrate control over litter decomposition

open access: yesFunctional Ecology, EarlyView.
Read the free Plain Language Summary for this article on the Journal blog. Abstract Elevated tropospheric ozone (O3) and nitrogen (N) deposition are concurrent atmospheric changes that strongly influence terrestrial carbon cycling, yet their combined effects on below‐ground decomposition remain poorly understood.
Xiaofan Hou   +8 more
wiley   +1 more source

Looking at Us Through Their Eyes. The Analytical Process from Ethnographic Perspectives1

open access: yesJournal of Analytical Psychology, EarlyView.
Abstract This article looks at the analytical situation through the Others’ eyes—through examples from contemporary ethnographies of foreign cultures. It discusses the following issues: a) The analogy between the ontological worlds of the dead, ghosts, animals and dreams in “primitive populations” and the analytical psychological descriptions of the ...
Stefano Carta
wiley   +1 more source

不同尺度下低山茶园土壤颗粒组成空间变异性特征

open access: yesShuitu Baochi Xuebao, 2006
利用地统计学方法,在两个尺度下对蘩顶山茶园土壤颗粒组成的空间变异性进行了研究。结果表明:(1)小尺度下土壤颗粒组成各粒级均具有强烈的空间相关性.其中粘粒的空间相关距最大.粗粉粒的空间相关距最小;土壤颗粒组成各粒级主要在东、东南和东北3个方向上具有较强的空间变异,除砂粒外的其它颗粒均在东南方向空间变异明显;各粒级的空间分布没有明显的规律可寻。(2)微尺度下只有粘粒具有强烈的空间相关性,砂粒具有中等空间相关性,其余粒级空间相关性很弱,粘粒空间相关距最小;除砂粒外的其它粒级在东南方向具有明显的空间变异 ...
冯娜娜   +4 more
doaj   +2 more sources

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