Environmental change in the mid-Boteti area of north-central Botswana: Biophysical processes and human perceptions

Increased interest in environmental change issues has led researchers to consider more integrated approaches to change dynamics. This paper examines change in terms of land degradation in north-central Botswana from both biophysical and human perspectives. Although seasonal and periodic droughts were prevalent, analysis of rainfall data over the past 70 years revealed no downward trend. However, indicators of declining productivity such as soil erosion, loss of vegetation cover, and a declining groundwater table were amply evident. The GIS analysis of remotely sensed data has shown that complete vegetation recovery after drought is not taking place, particularly in the south-central part of the study area. These areas contained the highest human and livestock population densities. The local people acknowledged facing increasing resource depletion and indicated drought as the main cause. Pressures on available resources, particularly during drought periods, appeared to have impeded the regenerative capacity of the natural vegetation cover, thereby inducing land degradation. This situation may not easily be rectified because of widespread poverty and inappropriate local perceptions of the solutions. Both of these hinder the adoption of sustainable land management.     

Need for recovery in offices: Behavior-based assessment

At work, people may experience fatigue and a depletion of mental resources. The subsequent need for recovery is generally assessed employing subjective reports on evaluative statements. In this paper, we explore whether it is possible to assess employees’ recovery needs with a systematic inspection of behaviors. The idea is based on Campbell’s paradigm (Kaiser, Byrka, & Hartig, 2010), which holds that individuals will perform more, and more difficult behaviors to recover from fatigue when their need for recovery is higher.     

Correlations of food distribution and patch size with agonistic interactions in female vervets (Chlorocebus aethiops) and patas monkeys (Erythrocebus patas) living in simple habitats

Food distribution is hypothesized to be important in determining the nature of female relationships within social groups of primates. When food limits female reproductive success, spatially clumped foods are expected to produce strong, linear dominance hierarchies within groups, whereas more spatially dispersed foods are expected to produce weaker or non-existent dominance hierarchies. The association between food distribution and competitive relationships presumably occurs because clumped foods are usurpable but dispersed foods are not. We examined the spatial distribution of food patches (trees) and patch size relative to feeding behavior and agonistic interactions in vervets and patas monkeys, two closely related and sympatric species that nonetheless differ in the strength of the female dominance hierarchy. Food patches of both patas monkeys and vervets were small in size and randomly distributed in Acacia drepanolobium habitat. In contrast, in A. xanthophloea woodland, the habitat type that was exclusively used by vervets, food patches were larger and more spatially clumped. These similarities and differences between and within species were correlated with similarities and differences in the strength and linearity of their dominance hierarchies. Patas monkeys and vervets in A. drepanolobium habitat had dominance hierarchies that were weakly defined because there were relatively few agonistic interactions between females. By contrast, in A. xanthophloea habitat, vervets had a stronger, linear dominance hierarchy characterized by a higher rate of agonistic interactions over food. The covariation of agonistic interactions with patch size is discussed in relation to depletion time, another characteristic that may covary with food distribution, and resource renewal rate, an important determinant of agonistic interactions in insectivorous birds, fishes, insects, and mammals. Received: 18 February 2000 / Revised: 5 September 2000 / Accepted: 26 September 2000     

含溴自由基对臭氧光解损耗的影响

本文研究了２５３．７ｎｍ的紫外光照条件下臭氧的损耗,以及在有Ｎ２和Ｏ２的体系中臭氧损耗的状况,得到不同条件下氧损耗的量子产额。并进一步测定了近似同层条件下溴损氧的量子产额为２４±１,计算出ＢｒＯ＋ＢｒＯ反应的两个分支反应通道的速率比为５．２５±０．２６。     

Effect of technology convergence for tablet PC on potential environmental impacts from heavy metals

The technology convergence integrating multiple devices into a single one is now a distinct trend in electronic industry. This trend can lead to a decrease in the use of rare and toxic heavy metals due to resource sharing, or an increase due to the application of new and auxiliary technology. This study investigates the effect of technology convergence for tablet PC on hazardous waste, resource depletion, and toxicity potentials from heavy metals in electronic devices, considering how many single devices (i.e., netbook computer, electronic dictionary, mp3 player, digital camera, cell phone, and vehicle GPS system) can be displaced by a tablet PC depending on users. The hazardous waste potential from heavy metals is examined with existing U.S. federal and California state regulations, and the resource depletion and toxicity potentials from heavy metals are evaluated based on life cycle impact assessments. The potentials of a specific tablet PC are compared to the total of those of displaced single products. Overall, the tablet PC has lower hazardous waste, resource depletion, and toxicity potentials from heavy metals. However, in case the tablet PC displaces only two or three single devices, it requires more gold, molybdenum, and vanadium. Therefore, technology convergence should take into account materials consumption and user behavior to develop more sustainable products.     

Conserving the abundance of nonthreatened species

Human modification of the environment is driving declines in population size and distributional extent of much of the world's biota. These declines extend to many of the most abundant and widespread species, for which proportionally small declines can result in the loss of vast numbers of individuals, biomass, and interactions. These losses could have major localized effects on ecological and cultural processes and services without elevating a species’ global extinction risk. Although most conservation effort is directed at species threatened with extinction in the very near term, the value of retaining abundance regardless of global extinction risk is justifiable based on many biodiversity or ecosystem service metrics, including cultural services, at scales from local to global. The challenges of identifying conservation priorities for widespread and abundant species include quantifying the effects of species’ abundance on services and understanding how these effects are realized as populations decline. Negative effects of population declines may be disconnected from the threat processes driving declines because of species movements and environment flows (e.g., hydrology). Conservation prioritization for these species shares greater similarity with invasive species risk assessments than extinction risk assessments because of the importance of local context and per capita effects of abundance on other species. Because conservation priorities usually focus on preventing the extinction of threatened species, the rationale and objectives for incorporating declines of nonthreatened species must be clearly articulated, going beyond extinction risk to encompass the range of likely harmful effects (e.g., secondary extinctions, loss of ecosystem services) if declines persist or are not reversed. Research should focus on characterizing the effects of local declines in species that are not threatened globally across a range of ecosystem services and quantifying the spatial distribution of these effects through the distribution of abundance. The case for conserving abundance in nonthreatened species can be made most powerfully when the costs of losing this abundance are better understood.     

Do not like it when you need it the most: Examining the effect of manager ego depletion on managerial voice endorsement

This paper advances the understanding of managerial voice endorsement based on a self‐regulation perspective. We suggest that although managers might potentially benefit more from employees' upward voice when they are more depleted, they are paradoxically less likely to diligently process or endorse such voice under ego depletion. We draw from ego depletion theory and argue that when managers are more depleted of their self‐control resources, they will spend less cognitive effort in processing voice. In turn, they tend to reject employee voice due to status quo bias and confirmation bias. We further suggest that the detrimental effect of ego depletion on voice endorsement is stronger when the voicing employee is perceived as having low expertise. We conducted an experience sampling study surveying 62 managers about voice events they encounter at work over 10 days (Study 1) and an experiment with 198 managers (Study 2). These two studies support our hypotheses. We discuss the theoretical and practical implications of our findings.     

生态工业园区--资源枯竭地区的新型工业化道路

系统描述了东北老工业基地以及资源枯竭地区目前发展所面临的困境，并以具体的实例说明了生态工业园区在促进上述地区走上新型工业化道路中的重要作用。     

大气中CH_4和N_2O浓度变化对氟氯碳化合物损耗O_3及ODP的影响

用计数物种法研究了ＣＨ_４、Ｎ_２Ｏ大气浓度的增长对氟氯碳化合物损耗Ｏ_３过程的影响。在０～２０ｋｍ大气范围内，ＮＯ_Ｘ增加幅度最大，引起这一区域的Ｏ_３有较大增长，ＨＯ_Ｘ浓度有所降低使ＨＣＦＣ_Ｓ在该区域的分解速率大为降低；在平流层中上层，由于ＣＨ_４、ＨＯ_Ｘ和ＮＯ_Ｘ的增加，使得对Ｃｌ原子多种储库分子有较大幅度的增加，氟氯碳化合物对臭氧的消耗能力因此有所减少。微量成分对臭氧消耗潜势（ＯＤＰ）值的影响幅度不大、方向也不确定。     

ADOPTION OF WATER-SAVING PRACTICES BY IRRIGATORS IN THE HIGH PLAINS1

ABSTRACT: The High Plains has been viewed as an immense garden because of its highly productive agricultural system based on irrigation. But there is concern that the aquifers are being depleted and that the region may be returning to its natural state of a vast shortgrass prairie. Efforts to avoid this scenario and to ensure continued survival of the integrated agribusiness economy focus on conserving water in irrigation. This paper examines the adoption of 39 water-saving practices for ten counties in Kansas, Nebraska, Oklahoma, and Texas. The frequency of adoption was estimated from a survey of 709 irrigators, and the variance was found primarily to be a function of location and secondarily to be influenced by number of wells, type of irrigation system, depth to water, age, and education. Locational differences remained strong even when the influence of secondary factors were controlled.