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The relationship between biodiversity and ecosystem functioning (BEF) is a central issue in ecology, and a number of recent field experimental studies have greatly improved our understanding of this relationship. Spatial heterogeneity is a ubiquitous characterization of ecosystem processes, and has played a significant role in shaping BEF relationships.

The relationship between biodiversity and ecosystem functioning (BEF) is a central issue in ecology, and a number of recent field experimental studies have greatly improved our understanding of this relationship. Spatial heterogeneity is a ubiquitous characterization of ecosystem processes, and has played a significant role in shaping BEF relationships. The first step towards understanding the effects of spatial heterogeneity on the BEF relationships is to quantify spatial heterogeneity characteristics of key variables of biodiversity and ecosystem functioning, and identify the spatial relationships among these variables. The goal of our research was to address the following research questions based on data collected in 2005 (corresponding to the year when the initial site background information was conducted) and in 2008 (corresponding to the year when removal treatments were conducted) from the Inner Mongolia Grassland Removal Experiment (IMGRE) located in northern China: 1) What are the spatial patterns of soil nutrients, plant biodiversity, and aboveground biomass in a natural grassland community of Inner Mongolia, China? How are they related spatially? and 2) How do removal treatments affect the spatial patterns of soil nutrients, plant biodiversity, and aboveground biomass? Is there any change for their spatial correlations after removal treatments? Our results showed that variables of biodiversity and ecosystem functioning in the natural grassland community would present different spatial patterns, and they would be spatially correlated to each other closely. Removal treatments had a significant effect on spatial structures and spatial correlations of variables, compared to those prior to the removal treatments. The differences in spatial pattern of plant and soil variables and their correlations before and after the biodiversity manipulation may not imply that the results from BEF experiments like IMGRE are invalid. However, they do suggest that the possible effects of spatial heterogeneity on the BEF relationships should be critically evaluated in future studies.
ContributorsYuan, Fei (Author) / Wu, Jianguo (Thesis advisor) / Smith, Andrew T. (Committee member) / Rowe, Helen I (Committee member) / Arizona State University (Publisher)
Created2011
Description

The status of Earth’s diversity is deteriorating quickly which will continue to impact humans’ way of life, as well as every other living creature, in all regions of the world. However, there are organizations taking action to protect biodiversity on our planet. The Convention on Biological Diversity (CBD) is one

The status of Earth’s diversity is deteriorating quickly which will continue to impact humans’ way of life, as well as every other living creature, in all regions of the world. However, there are organizations taking action to protect biodiversity on our planet. The Convention on Biological Diversity (CBD) is one of those organizations and includes 196 signatories from around the world who are committed to strategies to preserve their biodiversity (Secretariat). Indeed, 98% of the parties which have participated in the Convention on Biological Diversity (CBD) have created national biodiversity strategies (NBS) and action plans (NBSAPs) (Secretariat). Yet, there are still countries that have yet to partake in these efforts. America continues to hold out against ratifying the CBD and remains the only developed country without a National Biodiversity Strategy. As an NBS for the U.S. is under consideration, my goal is to understand what works from previous plans. In particular, I focus on stakeholder engagement in Conservation Biodiversity Action Plans. Stakeholder engagement is important because, without it, there may be insufficient levels of integration of the action plans, which can lead to the failure of the CBDs conservation efforts. To address this question, I analyze the 193 strategies created for countries across the globe. My review describes the ways that stakeholders are engaged in National Biodiversity Strategies for CBD member countries. All plans mention some form of engagement. The most common types mentioned are ‘Education’, ‘Communication’, and ‘Training’. Examining the plans further reveals that most forms of engagement often are just mentioned and not completed. Close to 58% of the engagement forms are only completed about 50% of the time. Exceptions are surveys, interviews, and workshops, which are each completed in over 70% of plans that mention them. I then use this information to provide practical recommendations for creating an effective NBSAP for the United States.

ContributorsOlofsson, Elisa (Author) / Gerber, Leah (Thesis director) / Kroetz, Kailin (Committee member) / Sterner, Beckett (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2022-12
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Habitat fragmentation, the loss of habitat in the landscape and spatial isolation of remaining habitat patches, has long been considered a serious threat to biodiversity. However, the study of habitat fragmentation is fraught with definitional and conceptual challenges. Specifically, a multi-scale perspective is needed to address apparent disagreements between landscape-

Habitat fragmentation, the loss of habitat in the landscape and spatial isolation of remaining habitat patches, has long been considered a serious threat to biodiversity. However, the study of habitat fragmentation is fraught with definitional and conceptual challenges. Specifically, a multi-scale perspective is needed to address apparent disagreements between landscape- and patch-based studies that have caused significant uncertainty concerning fragmentation’s effects on biological communities. Here I tested the hypothesis that habitat fragmentation alters biological communities by creating hierarchically nested selective pressures across plot-, patch-, and landscape-scales using woody plant community datasets from Thousand Island Lake, China. In this archipelago edge-effects had little impact on species-diversity. However, the amount of habitat in the surrounding landscape had a positive effect on species richness at the patch-scale and sets of small islands accumulated species faster than sets of large islands of equal total size at the landscape-scale. In contrast, at the functional-level edge-effects decreased the proportion of shade-tolerant trees, island-effects increased the proportion of shade- intolerant trees, and these two processes interacted to alter the functional composition of the regional pool when the total amount of habitat in the landscape was low. By observing interdependent fragmentation-mediated effects at each scale, I found support for the hypothesis that habitat fragmentation’s effects are hierarchically structured.
ContributorsWilson, Maxwell (Author) / Wu, Jianguo (Thesis advisor) / Smith, Andrew (Committee member) / Hall, Sharon (Committee member) / Jiang, Lin (Committee member) / Cease, Arianne (Committee member) / Arizona State University (Publisher)
Created2018