It is well documented that following human occupation of a region, the surrounding environment may undergo drastic changes through vegetation pattern alterations, displacement of fauna, alteration of sedimentation and fluvial regimes, and changes to the composition of the underlying material. Many case studies of anthropogenicdisturbance have been conducted in New Zealand. One of the main outcomes of this research is to collate, contrast and compare this wealth of case studies to look for any underlying trends in timing, distribution and magnitude of disturbance nationwide. This thesis focusses on late Holocene records from the North Island, and compared the history of disturbance with that from the South Island (as per McWethy et al. 2010). Based on the combination of palynology, sedimentology and geochemistry, this review demonstrates the pace of disturbance observed in the North Island was very rapid following occupation, a trend also established in the South Island.
channels and ponds physically differed only by the depth. The distribution of only five species significantly differed in relation to these two putative habitats. Furthermore, no differences in terms of species diversity indices were found between channels and ponds. Even the multivariate anal- ysis of the overall benthic assemblages confirmed the high heterogeneity at small spatial scale, but it has also high- lighted the presence of some minor differences between channels and ponds. Assemblages appeared more hetero- geneous in channels compare to ponds. In ponds, depth appeared the leading factor determining the benthic com- munity structure, while species distributions along the channels was strongly correlated with the anthropogenicdisturbance, represented by water surface temperature affected by thermal power stations, and the land–seaward gradient, in terms of distance from the outlet into the sea. Altogether pollution and land–seaward gradients appeared more important compared to the habitat type (i.e. ponds VS channels) in controlling the multivariate distribution pat- tern of macrobenthos. Anthropogenicdisturbance gradients overlap natural gradient, here as well as in most of the transitional waters, and this could represent a confounding factor. However, the multivariate analysis and multiple regression approaches improve the discrimination capa- bility between natural and anthropogenic stress (Gamito 2008).
Animals make behavioural and reproductive decisions that maximise their lifetime reproductive success, and thus their fitness, in light of periodic and stochastic variability of the environment. Modelling the variation of an individual’s energy levels formalises this tradeoff and helps to quantify the population-level consequences of stressors (e.g. disturbance from human activities and environmental change) that can affect behaviour or physiology. In this study, we develop a dynamic state variable model for the spatially explicit behaviour, physiology and reproduction of a female, long-lived, migratory marine vertebrate. The model can be used to investigate the spatio-temporal patterns of behaviour and reproduction that allow an individual to maximise its overall reproductive output. We parametrised the model for eastern North Pacific blue whales Balaenoptera musculus, and used it to predict the effects of changing environmental conditions and increasing human disturbance on the population’s vital rates. In baseline conditions, the model output had high fidelity to observed energy dynamics, movement patterns and reproductive strategies. Simulated scenarios suggested that environmental changes could have severe consequences on the population’s vital rates, but that individuals could tolerate high levels of anthropogenicdisturbance. However, this ability depended on where, when and how often disturbance occurred. In scenarios with both environmental change and anthropogenicdisturbance, synergistic interactions caused stronger effects than in isolation. In general, larger body size offered a buffer against stochasticity and disturbance, and, consequently, we predicted juveniles to be more susceptible to disturbance. We also predicted that females prioritise their own survival at the
plant diversity and changing the species distribu- tion pattern. Blanko and Pereira (2015) evalu- ated the anthropogenicdisturbance on natural vegetation in fragmented forests and showed that protection of woodland habitats were necessary for conservation of plant richness in the remain- ing stands. Shaheen et al. (2001) investigated the effects of human exploitation on structural diver- sity and community composition in the subtropi- cal forests of India and demonstrated that density, basal area and the number of species were less than those in similar undisturbed stands. Furthermore, they mentioned that this destruction caused much pressure on Quercus ilex Linnaeus, Quercus dila- tata Lindley ex de Candolle, Pinus wallichiana A.B. Jackson, and Pinus roxburghii Sargent spe- cies. Despite abovementioned studies, Linares et al. (2011) stated that the species diversity of those stands that experienced low human intervention was five times more than species diversity in pro- tected areas. Moreover Shrestha et al. (2012) evaluated the effects of human-made disturbance on the vascular plant diversity in oak forests in Ne- pal and illustrated that all diversity indices were enhanced where forest disturbance was at inter- mediate level. On the other hand, the soil proper- ties of forest can be affected by human activities (Gömöryová et al. 2008). In the forest ecosystems tree and herb species could influence soil proper- ties and also there is an interaction between trees and soil, in other words, growth and production of trees depend on the soil fertility. In addition, the amount of mineralization and nitrification of or- ganic matter in soil is associated with species rich- ness (Augusto et al. 2002). Moreno et al. (2007) stated that harvesting of trees resulted in reduction of organic matter and soil quality; therefore, dis- turbance caused by human activities could change the composition, quality and quantity situation of tree species and as a result affect the soil properties in forest ecosystems. Latty et al. (2004) evaluated the influences of land-use history on soil charac- teristics and nutrient dynamics in northern hard- wood forests of the Adirondack Mountains. The results showed that anthropogenicdisturbance decreased the soil carbon and nitrogen pools com- pared to old-growth. Also, Borrelli et al. (2017) demonstrated that 45.3% of soil loss is caused by water erosion in the logged forests in Italy.
With the combination of the sedimentological and geochemical analysis in relation to the known human history at the site, the distinct band at 0.6 m in the core has been interpreted as a ‘mining layer’ whereby anthropogenic factors (i.e. mining) began drastically modifying the environment and therefore caused disturbance at the site. Using the radiocarbon date this core represented an environment with a slow accumulation rate of just 0.35 mm annually prior to human settlement. In the wider Paeroa area mining commenced at a large scale at ~1905, depending on the claim as discussed in Chapter 4. Two large flood events were documented in 1904 and 1907 which submerged the Paeroa township under 2 ft of water in some places (as stop banks weren’t constructed at this point in time [Watton, 2006]) implying this was the most likely time this sediment layer would have been deposited across the floodplains. Using this layer as a proxy of the beginning of human mining disturbance at the site gives a sedimentation rate of 5.26 mm per year.. This is 20 times greater than the previous rate (0.35 mm per year) of sediment accumulation at the site, indicating that a large level of disturbance has occurred. This pattern of a dramatic increase in sedimentation has been observed in case studies across the world (e.g. Knox, 2001; Xu, 2004; Ahmed & Ismail, 2008). Wei et al. (2005) found in the Bohai Gulf that the accumulation rate of muddy sands had increased from 34.3 mm per year to 40.6 mm per year between 1955 to 1963. In the Yellow River, China, over the course of 2,300 years the sedimentation has changed from 4 mm per year pre 550 AD to 20 mm per year to 1850 AD. In the last 150 years it has increased up to 80 mm per year (Xu, 2003). In central coastal California sedimentation rates were impacted as early as 1770, increasing from 10 mm pre 1770, to 20 mm per year to the present (Plater et al. 2006). This strongly supports the suggestion that the change in sedimentation observed in the Maori Road core was related to anthropogenicdisturbance in the form of mining activities at the site and in the wider region.
The third cohort has been recruiting since the 1980s. The recruitment of this cohort is restricted mainly to the central part of the study area around the mountain top and it is not associated with al- most any release events. Therefore, disturbance is not the reason for recruitment of this cohort. The most likely reason is the planting carried out in the study area in the 1970s (Archives of NP Šumava Kašperské Hory, Forest management plan Srní 1969–1978, Javoří Pila forest district). This thesis is supported by the spatial pattern analysis, which shows rather an inhibition of trees below 2 meters and random spatial association between trees and regeneration on plots with the youngest cohort. Trees were probably planted at some dis- tances and gaps were preferred for planting. Until now, not many naturally regenerated trees have likely exceeded the coring limit of 10 cm DBH since 1960.
Mixed-species flocks of birds are distributed world-wide and can be especially dominant in temperate forests during the non-breeding season and in tropical rainforests year-round. We review from a community ecology perspective what is known about the structure and organization of flocks, emphasizing that flocking species tend to be those particularly vulnerable to predation, and flocks tend to be led by species that are able to act as sources of information about predators for other species. Studies on how flocks respond to fragmentation and land-use intensification continue to accumulate, but the question of whether the flock phenomenon makes species more vulnerable to anthropogenic change remains unclear. We review the literature on flocks in East Asia and demonstrate there is a good foundation of knowledge on which to build. We then outline potentially fruitful future directions, focusing on studies that can investigate how dependent species are on each other in flocks, and how such interdependencies might affect avian habitat selection in the different types of human-modified environments of this region.
Defining the biodiversity consequences of forest loss, land- scape and within-forest disturbance. We limit the biodiver- sity consequences of forest loss to those that occur in defor- ested areas themselves, excluding any additional effects on remaining forests. Landscape disturbance then captures the combined edge, area and isolation effects that accompany the deforestation process. Within-forest disturbance refers to an- thropogenic disturbance events that are not inevitable conse- quences of forest loss or land cover change, including wild- fires, hunting and selective logging. Although often associ- ated with landscape factors, such as distance from forest edge, within-forest disturbance can occur independently of changes in forest cover or landscape configuration.
We assess disturbance types with a biological measure – taxa richness. We hypothesize that four disturbance treatments will evidence increasing severity in the following order: (1) mature (M) sites were forests more than 50 years of age and neither physical habitat nor thermal conditions were changed; (2) clearcuts (CC) had the entire canopy removed (no remaining shady corridor, but stream bed was not disturbed), changes in thermal conditions have been reported in similar conditions [13,14]; (3) high flow (HF) sites had bed material extensively rearranged and flooded banks, while riparian vegetation remained largely intact ; and (4) debris flow (DF) sites had bed, banks, and much of the canopy removed with a subsequent partial deposition of new bed material, but with about 25% bare bedrock as well, extensive changes in both physical habitat and thermal conditions occurred . All of the disturbed treatments had intact forest remnants situated upstream from the disturbance, which we assumed would provide sources for subsequent colonists. We hypothesized that canopy removal (treatments 2 and 4) would increase both autochthonous energy sources and temperature, and lead to higher densities and richness relative to the maturing forest. Whereas high flow would decrease richness due to deleterious disturbance of the streambed (no change in insolation), the debris flow increase due to insolation would be partially counterbalanced by the extremely negative effect of stream and bank removal.
BCD5 (60.31–59.55 m OD): Increases in the varieties of C. placentula, Staurosira capucina var. vaucheriae and P. brevistriata represent meso- eutrophic conditions in the lough (Denys 1991/2); Patrick and Reimer 1966, 1975). There is a noticeable presence of dystrophic species primar- ily represented by Achnanthes helvetica (Patrick and Reimer 1966, 1975) which is also oligohalo- bous and circumneutral. This might imply a continuation of the inwash of humic and fulvic acids into the lake and it is likely that these originate from disturbance surrounding the cran- nog or the surrounding area of the lake. C. placentula varieties are common on floating debris and plants that could have been washed in (Krammer and Lange-Bertalot 1991) or more likely may have been growing on the plants, timbers and mud surrounding the crannog. The start of this dystrophic phase coincides with the change in stratigraphy from an organic silty mud to an organic sandy mud and is dated at ca. 970 BP. The levels of Gomphonema spp. Decline in this zone suggesting circumneutral conditions were prevelent. At 0.5 m depth
Pinang River, one of the important rivers in Balik Pulau district in Malaysia, is heavily impacted by anthropogenic activities such as domestic activities, aquaculture and agriculture (DOE, 2008). The creeks flowing into the Pinang River, Balik Pulau receive untreated wastewater discharge directly from small villages situated along the river. The anthropogenic activities existing at the river upstream eventually affects the water quality of the river and may have serious impacts, in terms of water pollution, on the marine ecosystem.
Because traditional matrix models (Caswell, 2001) are formu- lated in discrete time, they generally have a birth- pulse structure. In this structure, all births and deaths are assumed to occur at the same moment in time, which usually corresponds to the transition from one age class to the next, and all individuals within a class are treated as identical. However, classes may be subdivided to reflect the different vital rates of disturbed and undisturbed animals (King et al., 2015). Most PCoD applications have used a simple Leslie ma- trix to predict the trajectory of a population under different scenar- ios of anthropogenicdisturbance (King et al., 2015; New et al., 2014; Schwacke et al., 2017). Matrix models historically assumed that vital rates are simply a function of an individual’s age or stage, but integral projection models (IPMs) account for the additional effects of con- tinuously varying traits (such as physical size) on vital rates (Ellner & Rees, 2006). In principle, a continuous measure of health or the amount of disturbance experienced by different individuals could be modeled as a fitness- related trait (Coulson, 2012). However, be- cause IPMs do not assign traits to specific individuals, individuals are
So far there is no unambiguous answer regarding the specific reasons for methane concentration growth in the atmosphere. Some scientists believe that the tropics have become more humid and, correspondingly, the amount of gas emission has increased. Someone talks about the impact of changes in agriculture. Others point to the rapid growth of gas production in the world, including the rectification boom of natural gas in North America and its periodic leakage. The global distribution of methane on our planet is shown in Figure 3. Methane concentration is higher in the Northern Hemisphere, due to more powerful natural and anthropogenic sources of methane.
The uncertainty relation, which displays an elementary property of quantum theory, was originally described by Heisenberg as the relation between error and disturbance. Ozawa presented a more rigorous expression of the uncer- tainty relation, which was later verified experimentally. Nevertheless, the operators corresponding to error and distur- bance should be measurable in the identical state if we follow the presupposition of Heisenberg’s thought experiment. In this letter, we discuss simultaneous measurability of error and disturbance and present a new inequality using error and disturbance in the identical state. A testable example of this inequality is also suggested.
13 Quintana-Ascencio 2004; Liu et al. 2005; Menges et al. 2006). For croton, this will require more information than we currently have. One of the mechanisms through which altered disturbance return intervals affect populations is by altering the variability of vital rates between disturbance phases (Morris et al. 2006). For example, for many disturbance-adapted species, including croton, the variability of recruitment between disturbance phases is high, with high recruitment immediately following disturbance and almost no recruitment between disturbances (Figure 1B). If disturbance frequency was to increase, it is possible that post-disturbance recruitment would decrease, due to insufficient time for mature plants to replenish the seedbank. This would in effect decrease the between-phase variability of this vital rate, and negatively affect the long- term population growth rate. On the other end of the disturbance frequency spectrum, long return intervals allow succession to reduce the survival of fire adapted plants by increasing vegetation structure and therefore competition for light. Based on the population declines we measured in our control plots on Big Pine Key that have not burned in 15 years, we can infer that a 15 year disturbance return interval is too long to maintain growing croton populations. In addition to increasing competition, long fire return intervals increase the threat of catastrophic wildfires. Unlike the frequent, low intensity fires that native species are adapted to, these catastrophic fires are generally much hotter and may result in population declines or even extinction. Hot fires can kill seeds in the seedbank and consume below ground resource stores thus limiting the
minor challenges, such as changes in taste or smell, can be sufficiently disruptive to cause harm when a patient has limited physiologic or social reserves. Like most who experience geriatric syndromes, our patient’s falls and subsequent injuries were multifactorial. Visual impairment, physical environment, and osteopenia all played a role; however, on this occasion, the added challenge of nocturia related to taste disturbance exceeded her capacity.