Spatial Heterogeneity of Driving Factors of Wind Erosion Prevention Services in Northern China by Large-Scale Human Land-Use Management

Large-scale human land-use management is an effective method for ecosystem restoration and wind erosion prevention service (WEPS) improvement. However, the spatial differences of driving factors and the feedback in subsequent management have received less attention. This study analysed the temporal and spatial changes in the WEPS in northern China from 2000 to 2015, classified the driving modes between the WEPS and environmental factors, distinguished the main driving factors, and proposed suggestions for successive projects. The results showed that, compared with 2000, the amount of WEPSs in 2015 increased by 12.60%, and forest and grassland in the WEPS-increased area was 1.34 times that in the declining area. There were east–west differences in the driving mechanism of WEPS improvement. In addition to climatic and topographic factors, the western division was mainly affected by changes in vegetation quality, whereas the eastern division was affected by the combined influence of vegetation quality and quantity. This study shows the necessity of land-use management and project zoning policies, and provides a reference for policy formulation and management of large-scale ecological projects.

Human land-use impacts viral diversity and abundance in a New Zealand river

Although water borne viruses have important implications for the health of humans and other animals, little is known about the impact of human land use on viral diversity and evolution in water systems such as rivers. We used metagenomic next generation sequencing to compare the diversity and abundance of viruses at sampling sites along a single river in New Zealand that differed in human land use impact, ranging from pristine to urban. From this we identified 504 putative virus species, of which 97% were novel. Many of the novel viruses were highly divergent, and likely included a new subfamily within the Parvoviridae. We identified at least 63 virus species that may infect vertebrates, most likely fish and water birds, from the Astroviridae, Birnaviridae, Parvoviridae and Picornaviridae. No putative human viruses were detected. Importantly, we observed differences in the composition of viral communities at sites impacted by human land use (farming and urban) compared to native forest sites (pristine). At the viral species level, the urban sites had higher diversity (327 virus species) than the farming (n=150) and pristine sites (n=119), and more viruses were shared between the urban and farming sites (n=76) than between the pristine and farming or urban sites (n=24). The two farming sites had a lower viral abundance across all host types, while the pristine sites had a higher abundance of viruses associated with animals, plants and fungi. We also identified viruses linked to agriculture and human impact at the river sampling sites in farming and urban areas that were not present at the native forest sites. Overall, our study shows that human land use can impact viral communities in rivers, such that further work is needed to reduce the impact of intensive farming and urbanization on water systems.

Inhabiting the World’s Largest Tropical Delta: Understanding Human-Environment Relationship from a Century-Long Archaeological Quest in Bangladesh

Due to the exceptionally rich tropical resource, the Lower Ganges-Brahmaputra basins have attracted people of diverse ethnic and geographical backgrounds for millennia. So far 524 protected sites in present Bangladesh indicate the busy human occupation in the world’s largest delta at least from 5th century BCE. Although systematic archaeology began in the 1870s there is still a paucity of knowledge about past human land use and livelihood strategies across this area, which is especially prone to floods, cyclones, and river migrations. Here we attempt a systematic survey of human-environment interactions in ancient deltaic Bangladesh. Revisiting the fragmentary information from archaeological records and epigraphic references produced through over a century-long archaeological legacy, this study is the first attempt at a synthesis of the changing relationships between ancient people and their environment elements including land, water bodies, flora and fauna.

Spatiotemporal changes in early human land use during the Holocene throughout the Yangtze River Basin, China

The contribution of early human activity to the increase in atmospheric CH4 content during the middle to late-Holocene is still debated. The quantitative reconstruction of past changes in land use by early rice agriculture is a key to resolving the issue, because large uncertainties still exist in current prehistoric land use estimates, owing to a lack of direct records. In this study, we used the combination of archaeological data (the area and distribution of archaeological sites) and an improved prehistoric land use model (PLUM) to determine the spatiotemporal changes in land use by rice agriculture throughout the Yangtze River Valley, China, which was the origin and centre of the development of rice cultivation. The results indicate that the area devoted to rice agriculture increased during 10–2 ka BP, and that a significant increase occurred at ~5 ka BP accompanied by a spatial expansion from the northern part of the valley to the entire valley. However, the rice land use area decreased slightly during 4–3 ka BP but then increased after 3 ka BP. We estimate that the CH4 emissions from the rice cultivated area in the Yangtze River Valley increased from ~0.001 (±0.001) to ~1.3 (±0.6) Tg/year during 10–2 ka BP, and the resulting atmospheric CH4 concentrations increased from ~0.004 (±0.002) to ~4.1 (±2.0) ppb, which accounted for 3 (±2)–9 (±5) % of the ‘anomalous atmospheric CH4 increase’ during 5–2 ka BP.

Influence of Late Holocene Climate Change and Human Land Use on Terrestrial and Aquatic Ecosystems in Southwest Madagascar

Madagascar’s biota underwent substantial change following human colonization of the island in the Late Holocene. The timing of human arrival and its role in the extinction of megafauna have received considerable attention. However, the impacts of human activities on regional ecosystems remain poorly studied. Here, we focus on reconstructing changes in the composition of terrestrial and aquatic ecosystems to evaluate the impact of human land use and climate variability. We conducted a paleoenvironmental study, using a sediment record that spans the last ∼1,145 years, collected from a lakebed in the Namonte Basin of southwest Madagascar. We examined physical (X-ray fluorescence and stratigraphy) and biotic indicators (pollen, diatoms and micro- and macro-charcoal particles) to infer terrestrial and aquatic ecosystem change. The fossil pollen data indicate that composition of grasslands and dry deciduous forest in the region remained relatively stable during an arid event associated with northward displacement of the Intertropical Convergence Zone (ITCZ) between ∼1,145 and 555 calibrated calendar years before present (cal yr BP). Charcoal particles indicate that widespread fires occurred in the region, resulting from a combination of climate drivers and human agency during the entire span covered by the paleorecord. Following settlement by pastoral communities and the disappearance of endemic megafauna ∼1,000 cal yr BP, grasslands expanded and the abundance of trees that rely on large animals for seed dispersal gradually declined. A reduction in the abundance of pollen taxa characteristic of dry forest coincided with an abrupt increase in charcoal particles between ∼230 and 35 cal yr BP, when agro-pastoral communities immigrated into the region. Deforestation and soil erosion, indicated by a relatively rapid sedimentation rate and high K/Zr and Fe/Zr, intensified between 180 and 70 cal yr BP and caused a consequent increase in lake turbidity, resulting in more rapid turnover of the aquatic diatom community. Land use and ongoing climate change have continued to transform local terrestrial and freshwater ecosystems during the last ∼70 years. The current composition of terrestrial and aquatic ecosystems reflects the legacy of extinction of native biota, invasion of exotic species, and diminished use of traditional land management practices.

Challenges and opportunities of area-based conservation in reaching biodiversity and sustainability goals

Area-based conservation is essential to safeguard nature’s diversity. In view of expanding human land use, increasing climate change and unmet conservation targets, area-based conservation requires efficiency and effectiveness more than ever. In this review, I identify and relate pressing challenges to promising opportunities for effective and efficient protected area governance and management, to enhance research, decision-making and capacity building in area-based conservation under uncertain future developments. I reveal that protected area management is particularly challenged by human land use, climate change, invasive species, and social, political and economic limitations. Protected area management often lacks the continuous availability of data on current states and trends of nature and threats. Biocultural conservation, climate-smart management and biosecurity approaches help to overcome challenges induced by human needs, climate change and invasive species, respectively. Economic valuation and shifts in funding priorities can boost protected area effectiveness and efficiency. In-situ monitoring techniques, remote sensing and open data infrastructures can fill data and information gaps for protected area planning and management. Moreover, adaptive management is an auspicious concept in the framework of systematic conservation planning to ensure the enduring effectiveness of protected areas despite unpredictable future developments. Post-2020 international biodiversity and sustainable development goals could be met earlier if protected areas were more effective. I consequently conclude with the need for a global information system that is to support area-based conservation by synthesizing challenges and opportunities for protected area management effectiveness and efficiency at the local to global level.

Allozyme and Other Aspects of Variation in the Genus Bulbinella in New Zealand

<p>This thesis examines some aspects of morphological, cytogenetic and allozyme variation in the six species of the genus Bulbinella in New Zealand. Because evidence was found suggesting that fragmentation and reduction of the habitat of some species of the study genus had occurred, aspects of the conservation status of Bulbinella were also investigated. Some of the morphological characters described and used by Moore (1964) to separate the species were employed in this study as well as other characters recorded by the author in actively glowing plants. Generally, the seven taxa could be successfully distinguished using selected morphological characters, although in some species or populations a range of morphological forms was observed. Increased human land use (mainly mining, farming and associated activities) has reduced some populations of Bulbinella to low numbers by destroying large areas of habitat. In some cases once vast areas of Bulbinella have been reduced to fragments or probably exterminated. The karyotypes of five of the seven taxa were determined and these were all consistent with published data. G-banding was achieved in only one slide from one plant. A total of four bands (restricted to two pairs of chromosomes) was observed in the entire chromosome complement of 14. Each band was located on a separate chromosome. Inflorescence material from 61 natural populations of Bulbinella in New Zealand was examined for enzyme activity using starch gel electrophoresis. Activity was detected for eight of a total of 43 enzyme stains. Three monomorphic and 11 polymorphic loci were resolved. While no completely fixed differences between all the taxa could be demonstrated, four almost fixed differences were found. In some instances where populations belonging to different species were not geographically separated by great distances (<50km) shared alleles between species were demonstrated, indicating that introgression had occurred and may still be taking place. Overall, the genetic distance (Nei 1978) within taxa was less than that between taxa. The dendrogram resulting from cluster analysis of Nei's unbiased genetic distances divided the genus into four groups, three of which corresponded to three currently recognised taxa. The other group contained the remaining four taxa. Although the component taxa of this cluster could be readily separated using morphological characters, they could not be distinguished using allozyme data. The endemic distribution of B. rossii (Campbell Island and Auckland Island Group) and fixed morphological differences justify its remaining a separate taxon. The formal raising of B. gibbsii var. gibbsii to a separate specific status is subject to the analysis of further samples of this taxon. B. angustifolia, B, talbotii, and B. gibbsii vat. balanifera also remain separate taxa, with B. gibbsii var. balanifera being raised to a separate specific status. B. modesta, which is genetically closely related to B. hookeri, becomes a sub-species of this taxon.</p>

Allozyme and Other Aspects of Variation in the Genus Bulbinella in New Zealand

<p>This thesis examines some aspects of morphological, cytogenetic and allozyme variation in the six species of the genus Bulbinella in New Zealand. Because evidence was found suggesting that fragmentation and reduction of the habitat of some species of the study genus had occurred, aspects of the conservation status of Bulbinella were also investigated. Some of the morphological characters described and used by Moore (1964) to separate the species were employed in this study as well as other characters recorded by the author in actively glowing plants. Generally, the seven taxa could be successfully distinguished using selected morphological characters, although in some species or populations a range of morphological forms was observed. Increased human land use (mainly mining, farming and associated activities) has reduced some populations of Bulbinella to low numbers by destroying large areas of habitat. In some cases once vast areas of Bulbinella have been reduced to fragments or probably exterminated. The karyotypes of five of the seven taxa were determined and these were all consistent with published data. G-banding was achieved in only one slide from one plant. A total of four bands (restricted to two pairs of chromosomes) was observed in the entire chromosome complement of 14. Each band was located on a separate chromosome. Inflorescence material from 61 natural populations of Bulbinella in New Zealand was examined for enzyme activity using starch gel electrophoresis. Activity was detected for eight of a total of 43 enzyme stains. Three monomorphic and 11 polymorphic loci were resolved. While no completely fixed differences between all the taxa could be demonstrated, four almost fixed differences were found. In some instances where populations belonging to different species were not geographically separated by great distances (<50km) shared alleles between species were demonstrated, indicating that introgression had occurred and may still be taking place. Overall, the genetic distance (Nei 1978) within taxa was less than that between taxa. The dendrogram resulting from cluster analysis of Nei's unbiased genetic distances divided the genus into four groups, three of which corresponded to three currently recognised taxa. The other group contained the remaining four taxa. Although the component taxa of this cluster could be readily separated using morphological characters, they could not be distinguished using allozyme data. The endemic distribution of B. rossii (Campbell Island and Auckland Island Group) and fixed morphological differences justify its remaining a separate taxon. The formal raising of B. gibbsii var. gibbsii to a separate specific status is subject to the analysis of further samples of this taxon. B. angustifolia, B, talbotii, and B. gibbsii vat. balanifera also remain separate taxa, with B. gibbsii var. balanifera being raised to a separate specific status. B. modesta, which is genetically closely related to B. hookeri, becomes a sub-species of this taxon.</p>