Results 21 to 30 of about 9,231 (113)

基于遥感生态指数的阿克苏地区生态质量时空变化及其驱动力

open access: yesShuitu Baochi Xuebao, 2023
为及时全面地监测阿克苏地区生态环境质量的时空变化,基于谷歌地球引擎(GEE)平台,利用MODIS多光谱传感器2005年、2010年、2015年、2020年的遥感数据构建遥感生态指数(RSEI),运用Moran指数、地理探测器等方法探究阿克苏地区生态环境质量时空演变及影响因素检测。结果表明:(1)2005-2020年阿克苏地区RSEI由0.24增至0.27,生态环境质量呈波动上升趋势,RSEI高值区主要分布于阿克苏地区北缘以及中部绿洲区,低值区主要分布于沙漠、戈壁等地。(2)2005-2020年 ...
李娟, 张永福, 余婷婷, 闫瑞齐
doaj  

Assessing differences among elasmobranch nurseries to aid conservation based on a genomics framework

open access: yesConservation Biology, EarlyView.
Abstract Elasmobranch nurseries often differ in environmental conditions, demographics, and use patterns. These differences affect the distribution of genetic variation among nurseries. However, conservation and management strategies often fail to account for such differences because they are difficult to characterize.
Dominic G. Swift   +8 more
wiley   +1 more source

瓯江口春秋两季大型底栖动物群落β多样性格局及其驱动因素分析

open access: yesHaiyang yu huzhao
β多样性是连接α多样性和γ多样性的重要枢纽,其格局及构建机制一直是生态学研究的热点,尤其是在海洋生态系统中对其的研究相对较少。从物种组成β多样性的角度出发,应用Mantel检验分析了瓯江口β多样性及其组分与地理距离的关系。通过基于矩阵的多元回归分析(multiple regression on distance matrices, MRM)、物种组成与环境因子之间的Mantel检验以及Shannon多样性指数与环境因子间的Spearman分析,综合探讨了构建瓯江口β多样性的主要环境因子。研究结果显示 ...
杨 玉澍   +5 more
doaj   +1 more source

Uncovering correlates of decline and critical refuges for a threatened terrestrial mammal

open access: yesConservation Biology, EarlyView.
Abstract Globally, the geographic ranges of numerous species are contracting. Identifying spatiotemporal patterns of threat impact can illuminate why species decline in some parts of their range but persist in others. We developed a correlative approach to identify species’ response thresholds and locate ecological refuge areas associated with ...
Natalya M. Maitz   +5 more
wiley   +1 more source

Integrating fossil data in ecological niche models to improve predictions of future habitat of Caribbean corals

open access: yesConservation Biology, EarlyView.
Abstract Ecological niche models (ENMs) are used to assess the abiotic preferences of species by linking their occurrences to the environmental conditions in which they live. We developed a fossil‐informed ENM framework that integrates mid‐Holocene and modern occurrences to test niche stability and reconstruct abiotic niche characteristics for four ...
Claire. M. Williams   +3 more
wiley   +1 more source

Comparing the Effects of Collaborative and Independent Writing on EFL Learners’ Individual Writing Performance: An Intervention Study

open access: yesInternational Journal of Applied Linguistics, EarlyView.
ABSTRACT Collaborative writing has attracted increasing attention in English as a Foreign Language (EFL) instruction due to its potential to enhance learners’ writing competence. However, few studies have examined the comparative effects of collaborative versus independent writing on EFL learners’ individual performance, especially in higher‐order ...
Ting Huang, Chenze Wu, Wenkang Zhang
wiley   +1 more source

嫩江中下游湿地生态环境敏感性分析及可持续管理对策

open access: yesShuitu Baochi Xuebao, 2002
对嫩江中下游湿地生态环境从自然驱动因子:流域地形地貌、地质构造和沉积特征、气候变化和人为驱动因子:人类开垦活动、水利工程等条件下进行了敏感性评价,在此基础上提出了湿地生态环境可持续性管理对策。
张艳红 张树文
doaj   +2 more sources

内蒙古赤峰地区环境因子对东北马鹿粪便皮质醇的影响

open access: yes野生动物学报, 2023
野生动物应激水平的非损伤性评估是了解野生动物对景观条件产生生理反应的重要方法。粪便皮质醇代谢产物(faecal cortisol metabolites,FCM)水平被认为是评价动物压力的潜在生物标志物。影响濒危东北马鹿(Cervus elaphus xanthopygus)应激的环境因子可能包括道路、植被、人为干扰和海拔等,因此采用酶联免疫分析法(ELISA)分析内蒙古高格斯台罕乌拉国家级自然保护区东北马鹿种群的粪便皮质醇激素数据,利用多元线性回归模型构建东北马鹿粪便皮质醇激素与环境因子的线性关系 ...
孙悦, 李剑峰, 张明海
doaj  

Compliance in Regulatory Gray Areas: The Case of the Organic Seed Standard

open access: yesPolicy Studies Journal, EarlyView.
ABSTRACT Adaptive regulations, designed to balance flexibility with accountability, can embed provisions that unintentionally leave room for firms to shirk on their responsibilities by exploiting flexibility. We call these provisions “regulatory gray areas,” and ask: how should we understand (non‐)compliance in adaptive regulatory settings?
Liza Wood   +3 more
wiley   +1 more source

晋西北丘陵风沙区50年林龄人工柠条林植被群落及其土壤特性变化

open access: yesShuitu Baochi Xuebao, 2022
为探究晋西北丘陵风沙区50年林龄人工柠条林植被群落特征及土壤环境因子的变化规律。在0(撂荒地), 12, 18, 40, 50年的时间序列上, 分析柠条生长性状、土壤含水量、土壤养分及植物群落特征等变化动态。结果表明: (1)随着人工柠条林种植年限的增加, 柠条盖度和株高在时间梯度上显著增加, 具体表现为, 种植后期(40~50年)的柠条盖度是种植前期(0~12年)的1.98倍, 柠条株高在种植后期(40~50年)是种植前期(0~12年)的1.48倍; 柠条密度随种植年限的增加而显著降低, 从种植前期 ...
刘婧   +4 more
doaj  

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