The Threat of Transformation: Quantifying the Vulnerability of Grasslands in South Africa

Abstract:  The ability to predict which areas of conservation importance are most vulnerable to transformation and to rank the relative damage that transforming land uses could cause to biodiversity are important components of an effective and realistic conservation planning process. We used the South African grassland biome as a case study to illustrate the assessment of vulnerability to land-use transformation through the construction of a "threat map." We identified the dominant transforming land uses and created suitability models based on area appropriateness for each. Land uses were scored according to their expected relative impacts on biodiversity, with a framework that included compositional, structural, and functional components. This information, once combined, resulted in a map that highlighted the areas most vulnerable to transformation in terms of the likelihood of their transformation and the impact on their biodiversity. We propose that such an analysis of the threat of transformation, in combination with species-representation approaches, will aid the integration of conservation planning theory and decision making. This approach can be applied at any scale and in any region with a robustness and accuracy dependent on data quality, resultant suitability models, and comprehension of how land uses affect an area's biodiversity.     

Relating chronic toxicity responses to population-level effects: A comparison of population-level parameters for three salmon species as a function of low-level toxicity

Standard laboratory toxicity tests assess the physiological responses of individual organisms to exposure to toxic substances under controlled conditions. Time and space restrictions often prevent the assessment of population-level responses to a toxic substance. Contaminants can affect various biological functions (e.g. growth, fecundity or behavior), which may alter different demographic traits, leading to population-level impacts. In this study, immune suppression, reproductive dysfunction and somatic growth impairment were examined using life history matrix models for coho salmon (Oncorhynchus kisutch), sockeye salmon (Oncorhynchus nerka) and chinook salmon (Oncorhynchus tshawytscha). Our intent was to gauge the relative magnitude of response to toxic effects among species and between life history stages, not provide a specific estimate of population growth rate or abundance. Effects due to immune suppression were modeled as reductions in age-specific survival. Toxic impacts on reproductive function were modeled as a 10% reduction in reproductive contribution for all reproductively mature age groups. Model runs that examined the effect of somatic growth reduction on population parameters incorporated both survival and reproductive impacts. All impacts were modeled as 10% reductions in the affected population demographic parameters. First-year survival and reproductive impacts produced similar population growth rates (λ), but resulted in different sensitivity and stable age distributions. Modeled somatic growth reduction produced additive effects on survival and reproduction. Toxic stressors producing similar changes in λ did not necessarily produce similar changes in the age distributions. Sensitivity and elasticity analyses demonstrated that changes to the first-year survival rate produced the greatest per-unit effect on λ for each species. Alteration in abundance of mature females also strongly influenced λ. Differences observed between species showed that the number of reproductive ages and time to reproductive maturity were important components for population-level responses. These results emphasize the importance of linking toxicity responses at low concentrations to the demographic traits they affect, and help to highlight the toxicity tests that are more suitable for assessing impacts on the focal species. Additionally, life history modeling is a useful tool for developing testable hypotheses regarding impacts on specific populations as well as for conducting comparisons between populations.     

RECOVERY OF “LOST” STORM WATER FROM LOCAL WASH BEDS1

ABSTRACT: Most of the precipitation that falls is unused because it never reaches a stream or recharges an underground supply. This storm water evaporates and is transpired and consumed by plants. Described below are pertinent legal principles and the concept for a small-scale system to capture and store some of this “lost” storm water from the subflow of small gravelly washes that are not part of or connected with a stream system. The subsurface flow is interrupted by an elastomer faced earthen barrier (dam) and stored in a gravel bed. Both the barrier and the gravel storage bed are situated below the surface of the wash bed. If the gravel bed is not underlain by a natural substratum that is relatively impervious, it is either placed on a liner of suitable compacted clay or is underlain with an elastomeric membrane to limit the downward infiltration and loss of the stored water. A system may be used to capture and store sub-flow after surface flow has ceased and during periods of drought; to supply household and irrigation water; to exercise Winters Doctrine rights; and to replace small dams and surface impoundments by underground storage of the captured water to ensure a more reliable and sanitary supply for livestock and wildlife. A system is most effective in desert regions where (or when) both stream and ground water are unavailable; where rainfall is infrequent, but in storms resulting in rapid runoff; and where land surface topography and morphology coincide to form sites that permit the productive use of a system. A system should not be installed without sound legal and hydrological advice. Careful engineering is essential to the safe and proper design of a system, especially its subsurface barrier.     

中国古代城市防火减灾措施研究

论文探讨并整理出中国古代城市发展中形成一套行之有效的防火措施。这些防火技术具有一定的科学性．     

中外沼气发展史略

产甲烷菌是一种古细菌(Archebacteria),有机物在厌氧条件下的产甲烷现象早在远古便有。而有文字记载的人类发现、认识以及研究开发并利用厌氧消化产生沼气的历史还是近两千年内的事情。本文通过大量史料、史实,从化学、生物、地质和比较历史学的角度,论证了西汉四川“火井”浅层生物生成气与沼气在形成机理上的相同性,从而提出了中国是世事上最早发现并利用沼气的国家(年代可追朔到公元前一世纪)的新观点,这一研究结果比以往中国沼气史的计算方法提早了约2000年。本文还用详尽的文字论述了中外沼气的发现、沼气实验,厌氧消化工艺研究及人工制取沼气技术的发展史。     

Past and future perspectives upon landscape instability in Cumbria, northwest England

Geomorphic and lacustrine evidence is used to identify phases of landscape instability in Cumbria, northwest England, British Isles. The temporal and spatial pattern of erosion is used alongside palaeovegetation data from across the region to elucidate the causes of landscape instability in the late Holocene. The lines of evidence include changes in sediment accumulation rate and provenance within the region’s lakes; the hillslope alluvial fan and gully incision record; the lowland fluvial geomorphic record; and pollen analytical data for the late Holocene vegetation history. The sediment supply driven hillslope and lacustrine records suggest that only the 1,200–800 BP and post 600–500 BP erosion episodes were both catchment-wide and directly affected upland hillslopes, with the earlier phases after 5,200 and 3,000–1,600 BP on a lower scale and more restricted spatially. These episodes coincide with major expansions or changes in anthropogenic activity during Neolithic, Iron Age and Romano-British, Norse and late Medieval times. The projected future trajectories of changes in both climate (UKCIP scenarios) and landuse (CAP reform and ESA status) appear unlikely to increase landscape instability, although a shift to greater incidence of storms and high magnitude flood events clearly could. The past shows that the largest increases in erosion and sediment movement occur in the wake of major intensifications in land pressure that primarily affect previously wooded or protected hillslopes, circumstances that land management strategists should mitigate against.     

Relationships between Sensitivity to Agricultural Intensification and Ecological Traits of Insectivorous Mammals and Arthropods

Abstract: We tested the hypothesis that variation in the sensitivity of animals to habitat change is explained by ecological traits (life‐history traits, trophic level, and mobility). We measured the sensitivity of insectivorous mammals (shrews and bats) and their prey (arthropods active at the soil surface and nocturnal aerial arthropods) to three aspects of agricultural intensification in a matched‐pair experimental design: increased use of agrochemicals (comparison of organic and conventional cereal crops, with pairing for the size of the boundary hedge), change in grassland management from hay to silage (with pairing for the size of the boundary hedge), and increased field size due to hedgerow loss (with boundary‐field comparisons as a proxy). We assessed the sensitivity of taxa as the difference in their relative abundance between pairs of high‐ and low‐intensity sites for each aspect of agricultural intensification. We used phylogenetically informed analyses to explore cross‐species relationships between our measures of sensitivity and seven ecological traits of animals (e.g., trophic level, mobility, and reproductive rate). Several traits were related to the sensitivity of animals to agricultural intensification. These traits were mainly associated with fast life histories (high reproductive output and low trophic level) and low mobility. Trophic level of adults was related to sensitivity to habitat change for all three aspects of agricultural intensification, but the direction of the relationship differed between the three aspects of intensification. The significance of the relationship between other ecological traits and sensitivity to intensification varied for the three aspects of agricultural intensification. Our results show that some ecological traits can be used to preselect taxa that are predicted to be sensitive to habitat change, and their sensitivity can be tested empirically for use as biotic indicator taxa. Understanding which traits are related to sensitivity to habitat change is vital because sensitivity is important in determining a taxon's ability to survive in dynamic environments.     

Evaluating environmental education,citizen science,and stewardship through naturalist programs

Amateur naturalists have played an important role in the study and conservation of nature since the 17th century. Today, naturalist groups make important contributions to bridge the gap between conservation science and practice around the world. We examined data from 2 regional naturalist programs to understand participant motivations, barriers, and perspectives as well as the actions they take to advance science, stewardship, and community engagement. These programs provide certification‐based natural history and conservation science training for adults that is followed by volunteer service in citizen science, education, and stewardship. Studies in California and Virginia include quantitative and qualitative evaluation data collected through pre‐ and postcourse surveys, interviews, and long‐term tracking of volunteer hours. Motivations of participants focused on learning about the local environment and plants and animals, connecting with nature, becoming certified, and spending time with people who have similar interests. Over half the participants surveyed were over 50 years old, two‐thirds were women, and a majority reported household incomes of over $50,000 (60% in California, 85% in Virginia), and <20% of those surveyed in both states described themselves as nonwhite. Thus, these programs need to improve participation by a wider spectrum of the public. We interviewed younger and underrepresented adults to examine barriers to participation in citizen science. The primary barrier was lack of time due to the need to work and focus on career advancement. Survey data revealed that participants’ ecological knowledge, scientific skills, and belief in their ability to address environmental issues increased after training. Documented conservation actions taken by the participants include invasive plant management, habitat restoration, and cleanups of natural areas and streams. Long‐term data from Virginia on volunteer hours dedicated to environmental citizen science show an increase from 14% in 2007 to 32% in 2014. In general, participants in the naturalist programs we examined increased their content knowledge about ecosystems, had greater confidence in conserving them, and continued to engage as citizen scientists after completing the program.     

广东使用化肥88年的历史回顾

本文对广东使用化肥８８年（１９０５—１９９２）的历史及现状、肥效演变和存在问题等作了简要的回顾，并提出了有关建议。我省各种作物产量的不断增长与化肥用量的不断增加及其合理施用密切相关。如何利用好化肥仍是农业科技工作者今后的一种职责。     

Legal requirements for risk and vulnerability assessments in Norwegian land-use planning

Land-use planning has been promoted as an important tool for adaptation to climate change. However, its success depends on effective communication between researchers and decision-makers. A “risk and vulnerability assessment” (RVA) is one method to facilitate the interaction between the groups. RVAs have been performed in Norwegian land-use planning for about 20 years, and been mandatory for new development the last few years. The first part of the article reviews the history and current legal regulation of RVAs in Norway. Continuing, the main part discusses the distribution of authority and responsibility for different parts of the process and result. The key finding is that significant decisions are deferred to municipal discretion, for example, the necessity (if doubtful) and scope of the assessments. Other topics (such as the burden of costs and eligible performers) are largely unregulated, prompting some arguments about the need for further legislative effort.