The use of scaled chrysophytes in long term monitoring programs for the detection of changes in lakewater acidity

The addition of a biomonitoring component to a routine chemical monitoring program would enhance the potential of the monitoring effort to measure shifts in lakewater acidity. We provide evidence that changes in the species composition of scaled chrysophytes can provide an effective means for identifying and quantifying changes in lakewater acidity. As a result, it is consluded that a scaled chrysophyte component would provide an excellent addition to a long term monitoring effort. Specific and subspecific taxa of scaled chrysophytes are differentially distributed along a pH gradient. The distributions along a pH gradient of many of the well defined and cosmopolitan taxa are summarized and the taxa arranged into different pH groups. The importance of pH, relative to other variables, in controlling the distribution of scaled chrysophytes is discussed utilizing evidence from both neolimnological and paleolimnological studies. A plan for the incorporation of a biomonitoring component utilizing scaled chrysophytes into a long term monitoring program for acidity is outlined. The plan includes analyses using discrete water samples, sediment traps and sediment cores. Several programs are outlined and discussed based on the frequancy of sampling events.     

Brown hyaenas on roads: Estimating carnivore occupancy and abundance using spatially auto-correlated sign survey replicates

Carnivore survey protocols that properly address spatial sampling and detectability issues are seldom feasible at a landscape-scale. This limits knowledge of large-scale patterns in distribution, abundance and their underlying determinants, hindering conservation of globally threatened carnivore populations. Occupancy analysis of data from logistically efficient sign surveys along consecutive road segments (spatially auto-correlated replicates) offers a potential solution. We adapted and applied this newly-developed method over 62,979 km² of human-modified land in South Africa. Our aims were to (1) generate unbiased estimates of brown hyaena occupancy and abundance (2) investigate two suspected determinants of occupancy using a combination of biological and socio-economic sampling techniques, and (3) use simulations to evaluate the effort required for abundance and occupancy estimates with acceptable bias, precision and power. Brown hyaena occupancy was estimated at 0.748 (±SE 0.1), and estimated overall density in agricultural land (0.15/100 km², ±SE 0.08) was an order of magnitude lower than in protected areas. Positive attitudes to carnivores and presence of wildlife farms exerted strong positive effects on occupancy, so changes in these factors may well exert monotonic impacts on local metapopulation status. Producing reliable occupancy and abundance estimates would require ?6 replicates and ?12 replicates per site respectively. Detecting 50% and 30% declines in brown hyaena occupancy with adequate power would require five annual surveys at ?65 sites and ?125 sites respectively. Our results suggest that protocols based on spatially auto-correlated sign survey replicates could be used to monitor carnivore populations at large, and possibly even country-wide spatial scales.     

Effect of Episodic and Regular Sewage Discharges on the Water Chemistry and Macroinvertebrate Fauna of a Mediterranean Stream

Physical, chemical and biological parameters were used to investigate the effects of regular and episodic sewage inputs,either domestic or industrial, on the water quality of a smallMediterranean stream (River Magro, eastern Spain). Although results from chemical analyses were useful for monitoring waterquality in areas where sewage discharge was regular, episodic andlocalised discharges from industries or farms were not detected by chemical analyses because sampling was performed seasonally. An adequately small number of macroinvertebrate taxa were foundto indicate water quality changes within R. Magro, and the presence/absence and relative abundance of these taxa can be usedas a simple, rapid, low cost method for detecting changes in water quality. Macroinvertebrates are highly sensitive to episodic sewage discharges, which are difficult to detect by classical physical and chemical monitoring.     

Rapid monitoring of species abundance for biodiversity conservation: Consistency and reliability of the MacKinnon lists technique

Effective monitoring of biodiversity for conservation requires information on spatial and temporal variation in species’ abundances. As conservation resources are limited, monitoring methods are required that enable rapid and cost effective data collection. There are many traditional methods of estimating absolute abundance, such as territory mapping and distance sampling. However, these typically require more time, expertise and finances than are available across much of the globe. This is especially so in the tropics, where high species richness, low densities of many species and structurally complex environments also make monitoring particularly challenging. The MacKinnon lists technique is a rapid assessment methodology designed for use in species rich environments. This method is typically used to estimate species richness, but it has also been suggested that it can generate consistent abundance indices, even when observer experience and environmental conditions vary. If this suggestion is correct, the MacKinnon lists method could be used to assess spatial or temporal changes in abundance using diverse survey data. Here, we provide the first detailed assessment of intra- and inter-observer consistency of the Mackinnon List method in generating species abundance indices that could be useful for conservation monitoring purposes. As a case study, we use one of the world’s most diverse avifaunas, that of the forested Bolivian Andes. We show that MacKinnon lists can provide species abundance indices that are consistent between observers of markedly different experience of the focal avifauna (zero to six years), and between assessments carried out in different stages of the breeding season, between which detectability of individuals differed significantly. We believe this is the first time that a biodiversity monitoring method has been demonstrated to produce consistent abundance indices for a highly diverse avian tropical assemblage. We also suggest that the MacKinnon lists methodology has the potential to be a very useful conservation monitoring tool for many taxa in species rich environments, such as the tropics.     

Composite sampling enhances the confidence of soil microarthropod abundance and species richness estimates

The quantification of abundance and species richness of soil microarthropods is most often severely hindered by extraordinary data variability, highly skewed frequency distributions, many extreme and zero counts, and small sample sizes. We developed a composite sampling technique to enhance the confidence of abundance and species richness estimates. Many soil cores (n ≥ 100) are sampled, animals extracted, the extracts pooled, mixed, and subsamples (aliquots) taken. Compared to the standard (separate sampling units), no microarthropods were lost or mechanically damaged during the compositing procedure. The confidence of abundance estimates was substantially greater in the composite than in the standard, although not for taxa of low abundance (< ≈ 10³ ind.m⁻²). Moreover, compositing was the superior technique in estimating species richness. The number of sampling units needed to recover a certain number of species with the composite was 70% of the standard method. We conclude that composite sampling is a promising alternative to the standard technique and may help to increase the generally low confidence of microarthropod field data. Finally, potential limitations of composite plans are discussed: a great number of field cores from an unbiased sampling plan have to be composited; comparisons between composites of unequal size should be avoided; all information on the variation among field cores is lost by compositing; parallel measurements of fauna and other variables in the same cores are not possible.     

Usefulness of volunteer data to measure the large scale decline of “common” toad populations

Measuring a species decline is pivotal to evaluate their conservation status, but an accurate assessment of demographic trends requires observations collected across broad spatial and temporal scales. Volunteers can help to collect information over large scales, but their data may be affected by heterogeneity for sampling efforts and protocols, which may influence detection probability. Ignoring this issue may conduct to misleading conclusions. Here we show that data collected by different volunteer groups can be integrated with measures of sampling efforts, to obtain information on large scale demographic trends. We collected data on 33 common toad (Bufo bufo) populations across Italy for the period 1993–2010. We used two approaches (meta-analysis; analysis of average change in population size) to evaluate the overall demographic trend. We incorporated measures of volunteer sampling efforts into analyses, to take into account changes in detection probability. Toad abundance significantly declined in the last decade. From 2000 to 2010, 70% of populations showed a strong decline, and only 10% increased. Trends were heterogeneous among populations, but taking into account sampling effort reduced heterogeneity by 40%. We detected a 76% cumulative average decline of toad populations, despite an increasing mean sampling effort. The widespread toad decline rises concern for its future, also because the causes remain unclear. Volunteer data can be extremely useful to identify large scale population trends, if information on sampling effort are recorded and used to adjust counts.     

Evaluating exuvia collection as a management tool for the federally endangered Hine’s emerald dragonfly, Somatochlora hineana Williamson (Odonata: Cordulidae)

Reliable population density estimates are crucial for monitoring endangered species. Many species are difficult to capture or range over large areas, making direct monitoring of populations through capture or observation extremely challenging. In such cases, indirect methods of assessing populations can be the only source of reliable information. We examined whether the discarded exoskeleton of the last larval instar (exuvia), left behind when dragonflies emerge into the adult stage, could be used to predict larval densities and provide life history information for the federally listed endangered, Hine’s Emerald Dragonfly (Somatochlora hineana). Using standardized protocols, we collected exuvia within six 2 × 2 m plots in an ephemeral wetland in Door County, Wisconsin during spring and summer of 1999 and 2000. S. hineana is a “summer emerger”, with more than 95% of the emergence occurring from late June until mid-July. Based on time of emergence and the flight period, adults appear to live a month or longer. The sex ratio at emergence did not differ significantly from a 1:1 ratio and emergence was synchronous between the sexes. Estimates of larval population density using exuvial data were similar to those obtained through intensive direct sampling for larvae. Exuvial collections provide a reliable estimate of larval population density, help link larval ecology to adult ecology and are a useful tool for assessing habitat suitability. Although sampling exuviae requires repeated searching on particular sites, less expertise and fewer people are required for this type of sampling, indicating that exuvial surveys can be a very effective tool for monitoring populations of endangered dragonflies.     

Frugal conservation: What does it take to detect changes in fish populations?

Many conservation projects have to develop practical and feasible ways to detect changes in populations. We compare the ecological information obtained using intensive monitoring of coral-reef fish populations with that which would be procured from less exhaustive sampling. At each of four sites in the Philippines, we surveyed all non-cryptic fish species in eight transects every month for up to 3 years. We first tested for changes across years and seasons in fish density, size and species richness. We then compared these results obtained by using all data to those obtained in simulated protocols that restricted effort in ways that were relevant in practical marine resource management. We demonstrate the potential for reducing time in the water (number of surveys or number of transects) or in the number of species surveyed (proportions of those that were easily identified or locally fished) with little loss of information. Bimonthly surveys detected most of the overall but few of the seasonal trends that were identified with monthly sampling; far fewer trends were detected with less frequent surveying. Similarly, most trends were detected when at least four transects were carried out monthly. Most trends were also detected when all possible easily-identified species or at least 75% of fished species were considered. Indeed, ability to detect overall trends remained high even when only fished species were considered in four transects monthly. We conclude that some selective sampling protocols can be sufficiently sensitive to detect important trends, and that the choice of protocol will depend on the objective of the research or management.     

The seven impediments in invertebrate conservation and how to overcome them

Despite their high diversity and importance for humankind, invertebrates are often neglected in biodiversity conservation policies. We identify seven impediments to their effective protection: (1) invertebrates and their ecological services are mostly unknown to the general public (the public dilemma); (2) policymakers and stakeholders are mostly unaware of invertebrate conservation problems (the political dilemma); (3) basic science on invertebrates is scarce and underfunded (the scientific dilemma); (4) most species are undescribed (the Linnean shortfall); (5) the distribution of described species is mostly unknown (the Wallacean shortfall); (6) the abundance of species and their changes in space and time are unknown (the Prestonian shortfall); (7) species ways of life and sensitivities to habitat change are largely unknown (the Hutchinsonian shortfall).Numerous recent developments in taxonomy, inventorying, monitoring, data compilation, statistical analysis and science communication facilitate overcoming these impediments in both policy and practice. We suggest as possible solutions for the public dilemma: better public information and marketing. For the political dilemma: red-listing, legal priority listing and inclusion in environmental impact assessment studies. For the scientific dilemma: parataxonomy, citizen science programs and biodiversity informatics. For the Linnean shortfall: biodiversity surrogacy, increased support for taxonomy and advances in taxonomic publications. For the Wallacean shortfall: funding of inventories, compilation of data in public repositories and species distribution modeling. For the Prestonian shortfall: standardized protocols for inventorying and monitoring, widespread use of analogous protocols and increased support for natural history collections. For the Hutchinsonian shortfall: identifying good indicator taxa and studying extinction rates by indirect evidence.     

Long-term monitoring of tropical bats for anthropogenic impact assessment: Gauging the statistical power to detect population change

Bats are ecologically important mammals in tropical ecosystems; however, their populations face numerous environmental threats related to climate change, habitat loss, fragmentation, hunting, and emerging diseases. Thus, there is a pressing need to develop and implement large-scale networks to monitor trends in bat populations over extended time periods. Using data from a range of Neotropical and Paleotropical bat assemblages, we assessed the ability for long-term monitoring programs to reliably detect temporal trends in species abundance. We explored the magnitude of within-site temporal variation in abundance and evaluated the statistical power of a suite of different sampling designs for several different bat species and ensembles. Despite pronounced temporal variation in abundance of most tropical bat species, power simulations suggest that long-term monitoring programs (?20 years) can detect population trends of 5% per year or more with adequate statistical power (?0.9). However, shorter monitoring programs (?10 years) have insufficient power for trend detection. Overall, our analyses demonstrate that a monitoring program extending over 20 years with four surveys conducted biennially on five plots per monitoring site would have the potential for detecting a 5% annual change in abundance for a suite of bat species from different ensembles. The likelihood of reaching adequate statistical power was sensitive to initial species abundance and the magnitude of count variation, stressing that only the most abundant species in an assemblage and those with generally low variation in abundance should be considered for detailed population monitoring.     

Estimating the Contribution of Sampling,Sample Pretreatment,and Analysis in the Total Uncertainty Budget of Agricultural Soil pH and Organic Carbon Monitoring

Monitoring of soil organic carbon (SOC) and pH is needed to manage soil protection and tackle possible degradation in support of, i.e, the upcoming European Soil Framework Directive. Harmonized monitoring procedures and protocols produced under the auspices of the International Organization for Standardization (ISO) and the European Committee for Standardization (CEN) will be recommended. The uncertainty contributions of sampling, sample pretreatment, and analysis in the monitoring of soil pH and organic carbon in agricultural parcels using these harmonized monitoring procedures have been studied.

A within-laboratory comparison between the different analytical methods and sample pretreatments was made on 451 soil samples for SOC and 150 samples for soil acidity. Thereafter, a field study was performed to evaluate the contribution of the sampling method. Finally, an interlaboratory trial (including sampling) was organized to assess the overall monitoring uncertainty.

The results indicate that the influence of different sample pretreatments (e.g., milling) in combination with different analytical methods (elemental combustion versus chemical oxidation) are the main contributions to the observed uncertainty in the monitoring of SOC. For the monitoring of soil acidity, a similar observation was made, showing that differences in the practical implementation of the analytical method (e.g., mechanical shaking) are the main contributions to the monitoring uncertainty. The monitoring uncertainties derived from an interlaboratory trial (including sampling) amounted to ±20% (95% confidence interval, CI) for SOC and ±0.3 pH units (95% CI) for soil acidity on an agricultural parcel.     

Measurement Uncertainty of Sulphur and Nitrogen Containing Inorganic Compounds By 1-Stage and 2-Stage Filter-pack Methods

The sampling and analysis properties of 1-stage and 2-stage filter-pack methods were studied in detail in monitoring of sulphur and nitrogen containing inorganic gases and particles (sulphur dioxide, sulphate, sum of nitric acid and nitrate and total ammonium). The limit of detection and the limit of quantitation for 24-h samples were estimated using the results of a short-term field experiment completed with available data from long-term monitoring and internal quality assurance. Furthermore, the combined expanded measurement uncertainty including sampling and analysis (U_tot) was estimated for filter-pack methods in order to give a tool for distinguishing long-term trends in air quality from the measurement variability. U_tot was found to be very near the analytical uncertainty when measuring higher air concentration levels, being ± 4.0% for sulphur concentrations?>?1.0 μg m^?3, ± 3.0% for sulphate concentrations?>?0.5 μg m^?3, ± 3.5% for the sum of nitrate and nitric acid concentrations?>?0.3 μg m^?3 and ± 4.5% for total ammonium concentrations?>?0.8 μg m^?3. At the lower air concentration range U_tot increases significantly due to the field blank values. The precision of the 24-h filter-pack sample results expressed by means of modified median absolute difference (M.MAD) and coefficient of variance (CoV) gave 8.3% for sulphur dioxide and 5.4% for particulate sulphate. For the sum of gaseous nitric acid and particulate nitrate the CoV was 5.5% and for total ammonium 4.3%. In addition the suitability of the 24-h filter-pack methods in weekly sampling was proved.     

Effects of repeated drought on soil microarthropod communities in the northern Chihuahuan Desert

 Soil microarthropods were sampled in plots centered on creosotebushes (Larrea tridentata) and in plots centered on mesquite (Prosopis glandulosa) coppice dunes. Nine plots in each area were covered by rain-out shelters with greenhouse plastic roofs which excluded natural rainfall and nine plots received natural rainfall. There were differences in the abundance of several mite taxa in soils from the mesquite coppice dune plots. Some taxa (Stigmaeidae, Nanorchestidae, and Entomobryidae) occurred in significantly lower numbers in the soils of the drought plots. Other taxa (Tarsonemidae and Cunaxidae) were more abundant in the drought plots in the mesquite coppice dunes. There were no significant differences in the abundance of any of the dominant taxa of soil microarthropods in the drought and control plots centered on creosotebush. In the creosotebush habitat, there were significantly fewer Prostigmata in the plots exposed to drought. In an area with both creosotebush and mesquite, there were no significant differences in microarthropod population responses to drought and in recovery from drought. The differences in responses of soil microarthropods to drought in creosotebush and mesquite habitats are attributed to the differences in soil stability, litter accumulations, and microclimate associated with the shrubs. Received: 29 December 1997     

基于遥感抽样的国家尺度农作物面积统计方法评估

国外从20世纪70年代已将遥感用于农业统计,中国从起步至今也有20多年的历史。遥感以其准确、及时、客观的优势推动了农业统计的进步,但对于遥感统计的精度评估一直不甚明确,影响了遥感监测的可信度和遥感技术优势的充分发挥。该文首先分析了目前国内外农业遥感统计的主要方法及其评估方式,针对中国大尺度农作物面积遥感统计方法的实际,采用多种指标对其进行评估,目的是对遥感统计调查的准确度予以明确的定义和计算。采用亚米级差分GPS采样获取足量样本的方法,对L andsat TM提取的水稻面积进行验证,基于原始的误差矩阵计算得出生产者精度为89.53%,用户精度为95.37%,总体精度为87.02%,地面实测数据和图像解译结果的相关系数为0.96;引入误差指标σ来直接反映分类结果较真值的总体误差,当σ〉0时,遥感解译结果较实际偏小,反之偏大,计算得到水稻遥感解译面积的σ值平均为0.084。     

Collembola diversity in the critically endangered Cape Flats Sand Fynbos and adjacent pine plantations

The replacement of indigenous vegetation by commercial alien plantations can strongly affect invertebrate species richness and composition. This has been demonstrated for some invertebrate taxa in the Fynbos vegetation of the Western Cape, but the response of litter-dwelling Collembola has not been documented. Here we compared the richness and abundance of litter-dwelling Collembola assemblages in Pinus radiata plantations and in adjacent rehabilitated Cape Flats Sand Fynbos (CFSF) in the Tokai Forest Reserve, Western Cape, South Africa. A total of 48 Collembola morphospecies was identified, of which 14 species were recorded exclusively from the pine plantations, and six exclusively from the CFSF. Abundance and morphospecies richness was higher in the pine plantations than in the CFSF, with 34 morphospecies found in the CFSF, and 42 morphospecies in the pine plantations. Fourteen species were likely invasive taxa, of which eight were found in CFSF, and 13 in the pine plantations. Multivariate analyses indicated significant differences in the assemblages of the two habitat types based on abundance, but using presence–absence data only, no difference was found. Significant relationships were found between springtail richness and abundance and site humidity, which differed between the CFSF (drier) and pine plantation (moister), likely accounting for the differences in richness and abundance among habitat types.     

Supply of tree-holes limits nest density of cavity-nesting birds in primary and logged subtropical Atlantic forest

Tree cavities are proposed to limit populations and structure communities of cavity-nesting birds. Although the greatest diversity of cavity-nesting birds is found in tropical and subtropical moist forests, little is known about how tropical logging affects the abundance of cavities or cavity-nesting birds. We compared the abundance of cavities and cavity nests between primary and selectively-logged subtropical moist Atlantic forest in Argentina, and conducted the first before-after controlled nest-box addition experiment to determine whether nest sites limit the breeding density of cavity-nesting birds in tropical or subtropical moist forest. Visual inspection of 86 cavities identified through ground-surveys revealed that only 19% were suitable for nesting birds, suggesting that cavity abundance may be overestimated in the literature on tropical forests. Suitable cavities were found in fewer than 1% of 1156 trees <60 cm dbh but 20% of 20 trees >100 cm dbh. Logged forest had half the basal area of primary forest, one third the density of large trees, nine times fewer cavities suitable for nesting birds, and 17 times fewer active nests. When we added nest boxes, nesting density increased on treatment plots but not on control plots in both logged and primary forest, suggesting that cavity supply can limit nest density even in relatively undisturbed forest. This is the first experiment to show how reduced cavity supply in logged tropical forest can limit breeding density of cavity-nesting birds. International initiatives such as forest certification should promote tropical timber management strategies that conserve large live cavity-bearing trees.     

Monitoring multiple species: Estimating state variables and exploring the efficacy of a monitoring program

Monitoring programs have the potential to identify population declines and differentiate among the possible cause(s) of these declines. Recent criticisms regarding the design of monitoring programs have highlighted a failure to clearly state objectives and to address detectability and spatial sampling issues. Here, we incorporate these criticisms to design an efficient monitoring program whose goals are to determine environmental factors which influence the current distribution and measure change in distributions over time for a suite of amphibians. In designing the study we (1) specified a priori factors that may relate to occupancy, extinction, and colonization probabilities and (2) used the data collected (incorporating detectability) to address our scientific questions and adjust our sampling protocols. Our results highlight the role of wetland hydroperiod and other local covariates in the probability of amphibian occupancy. There was a change in overall occupancy probabilities for most species over the first three years of monitoring. Most colonization and extinction estimates were constant over time (years) and space (among wetlands), with one notable exception: local extinction probabilities for Rana clamitans were lower for wetlands with longer hydroperiods. We used information from the target system to generate scenarios of population change and gauge the ability of the current sampling to meet monitoring goals. Our results highlight the limitations of the current sampling design, emphasizing the need for long-term efforts, with periodic re-evaluation of the program in a framework that can inform management decisions.     

Towards an ecologically-sustainable forestry in the Atlantic Forest

Since pristine Atlantic Forest remnants are vanishing, and biological reserves are in short, conservation of biodiversity will largely depend on proper management of the anthropogenic matrix. Here, we test (1) the effectiveness of ecologically-managed tree monocultures in maintaining Araucaria Forest biodiversity, (2) how this effectiveness change among taxa, and (3) we discuss management principles that can be used by the forestry industry in order to contribute positively to biodiversity conservation. The study was conducted in the São Francisco de Paula National Forest, southern Brazil, an environmental mosaic composed mostly of patches of Araucaria Forest and ecologically-managed monocultures of Araucaria, Pinus and Eucalyptus. Using standardized sampling methods in these four main habitats, we have recorded the richness and species composition of small mammals, birds, leaf-litter frogs, butterflies, galling insects, spiders, opiliones, flatworms, woody plants, epiphytic angiosperms, epiphytic ferns, lichens, and fruit-body producing fungi. Overall, we recorded 506 species in Araucaria Forest, 181 (36%) of which were exclusive of this habitat while 325 (64%) could be found in at least one monoculture. Distribution patterns of species richness and number of records across taxonomic groups showed that a large biodiversity can be found inside ecologically-managed plantations of Araucaria, Pinus, and Eucalyptus. For all studied taxa, except for epiphytic angiosperms and fruit-body producing fungi, more than half of the Araucaria Forest species could be found living on monocultures. We discuss how the actual management practices of the forest industry can be improved to contribute positively to the conservation of the Atlantic Forest biodiversity.     

巢湖十五里河不同河段沉积物古菌群落结构特征研究

[目的]为了探究城市河流沉积物古菌群落结构特征及其环境指示意义,[方法]应用高通量测序技术获取巢湖十五里河不同河段表层沉积物古菌群落组成,用冗余分析(RDA)和相关性分析等方法探究古菌群落结构特征与沉积物环境因子间的联系.[结果]十五里河表层沉积物古菌的优势菌门和次优势菌门分别是广古菌和奇古菌与深古菌,其相对丰度分别为...     

RAPD and isozyme analysis of genetic relationships between Carica papaya and wild relatives

The genetic origin of cultivated papaya is not clear. Wild relatives of papaya (Carica papaya) from central southern America were investigated using isozyme and RAPD analysis. Seven other species (including six from the genus Carica) were found to be relatively distant from papaya providing no indication of the genetic origin of papaya. Isozyme and RAPD data gave similar measures of genetic similarity within this group. C. papaya was about 70% dissimilar to the other Carica species by both methods. The other Carica species had average dissimilarities around 50%. Two species, C. pubescens and C. stipulata were much closer to each other with similarities of 87% by isozyme analysis and 82% by RAPD analysis. Although both methods gave similar measures for genetic distance the large number of RAPD markers available made RAPD analysis more reliable for analysis of the extremes (e.g. closely related taxa may show no isozyme differences and distant taxa may show no isozyme similarities).