Agroforestry systems as habitat for herpetofauna: is there supporting evidence?

The need to carry out biological conservation outside protected areas requires avoiding, minimizing or mitigating impacts brought about by habitat transformation upon the biota. Usually, forest plantations hold fewer species than the original forest. However, structurally complex plantations support more species and individuals than simpler ones. Here we test if this phenomenon occurs in amphibian and reptilian assemblages, analyzing information regarding their richness and abundance in forestry plantations from 14 countries and 72 case studies which compare species richness and abundance in plantations and forests. Among amphibians, species richness is lower in plantations than in forests while among reptiles there is no significant difference. The abundance of reptiles increases in plantations. Three studies dealt with reptile assemblages in relation to structural complexity of plantation, which suggest that species richness and abundance is higher in complex plantations. Despite accounting for 50 % of the terrestrial vertebrates, herpetological studies account for 15 % of the research available regarding the impact of plantation upon vertebrates, information deficiency that hampers decision-making on the conservation of herpetozoans outside protected areas.     

人类干扰对甘肃麻家寺保护站鸟类群落的影响

2004年11月~2005年1月,在兴隆山麻家寺保护站的6种生境(灌木、阔叶林、混交林、针叶林、农田和人工林)中共记录鸟类25种。鸟类物种总数以灌丛和人工林最高,均为15种。阔叶林最低,为10种。鸟类多样性最高的是灌丛,最低的是阔叶林。各种生境中的鸟类组成和优势物种差异较大,建议每种生境均保持一定面积,以便保护鸟类物种多样性。     

Agroforestry systems reduce invasive species richness and diversity in the surroundings of protected areas

The Serra do Brigadeiro State Park (PESB) is one of the largest fragments of Brazilian Atlantic Rainforest, and it is relevant for native species conservation. However, monocultures settled around the Park resulted in extensive open areas that facilitate the establishment of alien species on the PESB perimeter, which may threaten native species conservation therein, since biological invasion is the second main cause of global biodiversity loss. In this region, there are also farmers planting agroforestry systems (AFS), characterized by tree-based intercropping, which are structurally more similar to the Atlantic Rainforest reminiscent fragments present in the region and may limit local occurrence of potentially invasive exotic weeds for several reasons, such as the high levels of shade provided by trees, the groundcover that result from loss of tree leaves and the increased competition for belowground resources. This study aimed to test whether AFS limit exotic species establishment when compared to monoculture systems. Accordingly, three coffee monocultures and three agroforestry coffee plantations around the PESB were studied. In each of the six study areas, 30 plots of 1 m² were established between the lines of coffee plantation, where all species present were surveyed. In both treatments, rarefaction curves were constructed to evaluate native and exotic richness, and diversity of these two categories was estimated through Simpson index inverse (1/D). All 13 sampled exotic species were present in monocultures, but only three of them occurred in AFS. Besides, alien diversity in monocultures (\(1/D\) = 2.173 ± 0.011) was significantly higher than in AFS (\(1/D\) = 1.031 ± 0.001). Such changes in alien plant community between land-use show that AFSs limit invasive species establishment. Therefore, when planted around protected areas, AFS may contribute to the control of biological invasions and to biodiversity conservation.     

The effect of thinning on ground spider diversity and microenvironmental factors of a subtropical spruce plantation forest in East Asia

Currently, information about the effect of forest management on biodiversity of subtropical plantation forests in Asia is quite limited. In this study, we compared the spider community structures and guild compositions of subtropical Cryptomeria japonica plantation forests receiving different degree of thinning (0, 25 and 50 %) in central Taiwan. The ground spider diversities and environmental variables were sampled/measured once every 3 months for 1 year before thinning and 2 years after thinning. Results showed that before thinning spider compositions did not differ significantly among three plantation forest types. Two years after thinning, spider species and family compositions of three plantation forest types differed significantly. In all three plantation forest types, the spider composition differed from year to year, indicating existence of temporal variations in spider diversity. Ground hunters (increased 200–600 % in thinned forests), sheet web weavers (increased 50–300 % in thinned forests) and space web weavers (decreased 30–50 % in thinned forests) were the major contributors of the observed spider composition differences among plantation forests receiving different treatments. The stands receiving thinning treatments also had higher illumination, litter decomposition rate, temperature and understory vegetation density. Thinning treatments might have changed the structures of understory vegetation and canopy cover and consequently resulted in abundance and diversity changes of these guilds. Moreover, the heterogeneity in understory vegetation recovery rate and temporal variation of spider composition might further generate spider diversity variations in subtropical forests receiving different degree of thinning.     

Fungal diversity in coffee plantation systems and in a tropical montane cloud forest in Veracruz,Mexico

We compared the abundance, species richness and diversity of saprobic filamentous microfungi in the forest and in coffee plantation systems (with different biophysical structures of the vegetation and agricultural management) and evaluated the degree of similarity in species composition among these sites. Soil washing was used to isolate the saprobic filamentous microfungi. Emerging colonies were quantified and transferred to tubes with culture medium and then mounted on semi-permanent slides for identification under the microscope. From 90 samples and 4,500 inoculated soils particles, 415 species were distinguished. The genera Trichoderma, Penicillium, Fusarium, Chaetomium and Humicola were the most frequent in all study sites. The transformation of the tropical montane cloud forest in coffee plantation had no significant effect on the abundance, species richness and diversity of the saprobic filamentous microfungi. Effects of the biophysical structures of the vegetation and the agricultural management of the sites were only detected at the level of dominant genera (Fusarium, Trichoderma and Penicillium) and on the evenness. The low degree of similarity among the six sites suggests the existence of a high exchange of species.     

Assessment of tree diversity and above-ground biomass in coffee agroforest dominated tropical landscape of India's Central Western Ghats

The purpose of this study was to quantify the changes in tree diversity and above-ground biomass associated with six land-use types in Kodagu district of India's Western Ghats. We collected data on species richness,composition and above-ground biomass(AGB) of trees,shrubs and herbs from 96 sample plots of 0.1 ha. Totals of83 species from 26 families were recorded across the landuses. Tree species richness, diversity and composition were significantly higher in evergreen forest(EGF) than in other land-uses. Similarly, stem density and basal area were greater in EGF compared to other land-uses. Detrended correspondence analysis(DCA) yielded three distinct groups along the land-use intensities and rainfall gradient on the first and second axes, respectively. The first DCA axis accounted for 45% and second axis for 35% of the total variation in species composition. Together the first two axes accounted for over 2/3 of the variation in species composition across land-use types. Across the land-uses,AGB ranged from 58.6 Mg ha-1 in rubber plantation to327.3 Mg ha-1 in evergreen forest. Our results showed that species diversity and AGB were negatively impacted bythe land-use changes. We found that coffee agroforests resembled natural forest and mixed species plantation in terms of tree diversity and biomass production, suggesting that traditional coffee farms can help to protect tree species, sustain smallholder production and offer opportunities for conservation of biodiversity and climate change mitigation.     

Nestedness and modularity in fragmented Shasha Forest Reserve,southwestern Nigeria

Species co-occurrence and nestedness pattern in Shasha forest reserve were investigated with a view to determining the effect of interactions to species contribution. Three distinct sites (Gmelina arborea plantation, undisturbed forest, and Pinus carribaea (plantation) were selected in the forest reserve. Four 25 m × 25 m plots were established in each of the site within the forest reserve. Species enumeration, identification,, and distribution into families of the standing vegetation were carried out. Woody species represented the most diverse life form. Plant species diversity was highest in UF and lowest in Gmelina plantation. Differences in woody species composition among the three forest types were determined by non-metric multidimensional scaling (NMDS) analysis, analysis of similarity (ANOSIM), and similarity of percentages. Using z-score and NODF (a nestedness metric based on overlap and decreasing fill). Three modules were detected and modularity score Q = 0.2. The composition analyses (NMDS and ANOSIM) revealed a significant difference in the woody species composition among the forest types. Our research may contribute to understand species assemblage in one of the diverse forests of Africa. Current work highlighted species occurrence in Shasha forest and highlighted the importance of non-random pattern which could serve as framework for conservation perspective.     

Diversity and abundance of arbuscular mycorrhizal fungi spores under different coffee production systems and in a tropical montane cloud forest patch in Veracruz, Mexico

We evaluate the arbuscular mycorrhizal fungi (AMF) community as measured by spores in different coffee production systems (at the depth of 0?C15?cm). In addition, we analyze the similarities between the AMF communities in coffee production systems and those that occur in a tropical montane cloud forest patch in order to evaluate the capacity of coffee production systems to preserve the native AMF community. We carried out four samplings in five coffee production systems representative of a vegetation structure gradient, and in a forest. From 120 soil samples, 33 morphospecies were detected. In all the sites, the dominant morphospecies were Glomus clarum and Glomus sp. 3. We found no significant difference in AMF spore richness between sites. Diversity was similar in most of the coffee production systems. Significant differences were only detected in spore abundance; during the dry season the forest, shaded traditional rustic system and shaded simple system presented the highest spore abundance. With the exception of one species exclusive to the forest, the coffee production systems all share the same AMF species as the forest. The coffee production systems with the greatest similarity to cloud forest were the shaded traditional rustic system and the shaded simple system. It is suggested that control of weeds and fertilization could be important factors influencing the composition and abundance of AMF spores in coffee production systems.     

Semi-forest coffee cultivation and the conservation of Ethiopian Afromontane rainforest fragments

Coffea arabica shrubs are indigenous to the understorey of the moist evergreen montane rainforest of Ethiopia. Semi-forest coffee is harvested from semi-wild plants in forest fragments where farmers thin the upper canopy and annually slash the undergrowth. This traditional method of coffee cultivation is a driver for preservation of indigenous forest cover, differing from other forms of agriculture and land use which tend to reduce forest cover. Because coffee farmers are primarily interested in optimizing coffee productivity, understanding how coffee yield is maximized is necessary to evaluate how, and to what extent, coffee production can be compatible with forest conservation.Abiotic variables and biotic variables of the canopy were recorded in 26 plots within 20 forest fragments managed as semi-forest coffee systems near Jimma, SW Ethiopia. In each plot, coffee shrub characteristics and coffee yield were recorded for four coffee shrubs. Cluster and indicator species analyses were used to differentiate plant communities of shade trees. A multilevel linear mixed model approach was then used to evaluate the effect of abiotic soil variables, shade tree plant community, canopy and stand variables, coffee density and coffee shrub size variables on coffee yield.Climax species of the rainforest were underrepresented in the canopy. There were three impoverished shade tree communities, which differed in tree species composition but did not exhibit significant differences in abiotic soil variables, and did not directly influence coffee yield. Coffee yield was primarily determined by coffee shrub branchiness and basal diameter. At the stand level a reduced crown closure increased coffee yield. Yield was highest for coffee shrubs in stands with crown closure less than median (49 ± 1%). All stands showed a reduced number of stems and a lower canopy compared to values reported for undisturbed moist evergreen montane rainforests.Traditional coffee cultivation is associated to low tree species diversity and simplified forest structure: few stems, low canopy height and low crown closure. Despite intensive human interference some of the climax species are still present and may escape local extinction if they are tolerated and allowed to regenerate. The restoration of healthy populations of climax species is critical to preserve the biodiversity, regeneration capacity, vitality and ecosystem functions of the Ethiopian coffee forests.     

Thermal characteristics of amphibian microhabitats in a fire-disturbed landscape

Disturbance has long been a central issue in amphibian conservation, often regarding negative effects of logging or other forest management activities, but some amphibians seem to prefer disturbed habitats. After documenting increased use of recently burned forests by boreal toads (Bufo boreas), we hypothesized that burned habitats provided improved thermal opportunities in terrestrial habitats. We tested this hypothesis by conducting a radio telemetry study of habitat use (reported previously) and by using physical models that simulated the temperature of adult toads. We deployed 108 physical models in and adjacent to a 1-year old burn using a fully-replicated design with three burn severities (unburned, partial, high severity) and four microhabitats (open surface, under vegetation, under log, in burrow). Model temperatures were compared to a range of preferred temperatures in published studies. We found 70% more observations within the preferred temperature range of B. boreas in forests burned with high severity than in unburned areas. Burned forest was warmer than unburned forest across all microhabitats, but the largest relative difference was in burrows, which averaged 3 °C warmer in high-severity burn areas and remained warmer though the night. More than twice as many observations were within the preferred temperature range in high-severity burrows than in unburned burrows. Areas burned with high severity were still warmer than unburned forest 3 years after the fire. Habitat use of toads during the concurrent radio telemetry study matched that predicted by the physical models. These results suggest there are fitness-linked benefits to toads using burned habitats, such as increased growth, fertility, and possibly disease resistance. However, increased soil temperatures that result from wildfire may be detrimental to other amphibian species that prefer cooler temperatures and stable environments. More broadly, our data illustrate the use of physical models to measure and interpret changes that amphibians may experience from disturbance, and highlight the need for research linking vital rates such as growth and survival to disturbance.     

西双版纳布龙州级自然保护区两栖爬行动物多样性

2011年3月~2012年6月,经多次野外调查及访查,共记录到西双版纳布龙州级自然保护区两栖爬行动物74种。其中,两栖类34种,隶属于2目7科;爬行类40种,隶属于3目13科。两栖爬行动物中属国家I级重点保护2种;Ⅱ级重点保护4种。列入《国家保护的有益的或者有重要经济、科学研究价值的陆生野生动物名录》的有65种;云南特有种8种;西双版纳特有种4种。多样性指数分析表明,两栖爬行动物的多样性丰富,其多样性指数(D)分别为5.305 2和6.745 3。爬行类的DG-F高于两栖类,表明爬行类科属间多样性更高。据此,对该地区两栖爬行动物区系特征、保护措施等进行了分析。     

呼伦贝尔沙区4种生境土壤真菌群落结构和多样性

【目的】揭示呼伦贝尔沙区4种生境土壤真菌群落结构与多样性及其影响因素,探究不同生境对土壤真菌的影响。【方法】选择裸沙地、草地、樟子松人工林和樟子松天然林4种生境土壤真菌为研究对象,采用野外调查、ITS高通量测序结合RDA分析,比较分析不同生境土壤真菌种群特征。【结果】呼伦贝尔沙区土壤共检测到真菌5门22纲73目28科257属。其中,裸沙地和草地土壤优势真菌门为子囊菌门,樟子松人工林和天然林中优势真菌门为担子菌门。优势属共31属,裸沙地、樟子松人工林的优势属分别是被孢霉属和丝膜菌属,草地和天然林土壤中的优势属分别为被孢霉属和Archaeorhizomyces、红菇属和Geminibasidium。其中裸沙地和草地、樟子松人工林和天然林的土壤真菌进化分支更为接近。草地土壤真菌物种丰富度和个体数最高,分布最为均匀;裸沙地其次;樟子松天然林和人工林物种丰富度、个体数和多样性指数较低,分布也较为集中。土壤真菌群落分布的主要影响因子是土壤含水量,优势真菌属分布受多种环境因子影响,土壤孔隙度、含水量、有机质分别是被孢霉属、Archaeorhizomyces、丝膜属的主导影响因子,全磷则是红菇属和Geminibasidium的主导影响因子。【结论】呼伦贝尔沙区4种生境土壤真菌主要由子囊菌门和担子菌门组成,其中裸沙地和草地、樟子松人工林和天然林土壤真菌群落结构相似度较高。多类型草本植物使真菌种类增多且分布更为均匀,樟子松在一定程度上降低真菌数量和种类,并使其分布更为集中。不同生境的不同植被可以改变土壤性质,而土壤水分、营养元素及孔隙结构等土壤环境因素会直接影响4种生境土壤优势真菌属的代谢过程和功能特征,因此4种不同生境真菌群落结构及多样性呈显著差异。     

Predatory beetles in cacao agroforestry systems in Brazilian Atlantic forest: a test of the natural enemy hypothesis

The natural enemy hypothesis predicts a positive correlation between plant species diversity and natural enemy control. This study aimed to evaluate the role of traditional cacao agroforests, known as “cabrucas,” on the conservation of the predatory beetle community compared to that of monodominant rubber agroforests. Predatory beetles were sampled in three habitats in Southeastern Bahia, Brazil: cabrucas and rubber agroforests and native Atlantic forests. In each habitat, 18 10 m² plots were established, in which canopy cover was measured and beetles were sampled with a modified Malaise/window trap. Land use intensification did not affect the composition of predatory beetles, with the presence of widely distributed species that are also capable of colonizing simpler environments such as the rubber agroforest. Canopy cover had a positive effect on generalist predator diversity and we observed a reduction in the abundance and species richness of generalist predators with increasing habitat homogenization. Despite the simplified structure of the habitat, the remaining tree diversity and canopy cover in cabrucas supported a community of generalist predators similar to the one found in the native forest. Species diversity of bark beetle predators was higher in cabrucas, which may be due to the high diversity of bark beetles and the favorable abiotic conditions, whereas the low abundance of prey in the native forest and severe abiotic conditions in the rubber agroforest probably determined the lower diversity of generalist predators in these habitats. Cabrucas play an important role in the conservation, supporting a community of predatory beetles more similar to the one found in native forest and that is more effective at controlling populations of herbivores than in homogeneous rubber agroforests.     

Structure and diversity of small mammal communities of mountain forests in Western Carpathians

We sampled the small mammal (SM) community in mountain forest ecosystems of the Beskydy Mountains over 5 years in order to study associations with different types of forest habitat. Fourteen species were determined, three being eudominant (yellow-necked mouse—Apodemus flavicollis (45 %), bank vole—Clethrionomys glareolus (23.3 %) and field vole—Microtus agrestis (15.7 %) and one dominant common shrew—Sorex araneus (9.3 %)). Highest abundance was observed in young succession sites (plantations) with dicotyledonous plants dominant (>50 %) in the undergrowth. Highest diversity was observed in plantations and primeval forests. Lowest total abundance and diversity were observed in mature monocultures. Significant differences in diversity were only found between old monocultures and other sites. Using a faunistic similarity index, two basic SM community groups were determined: those inhabiting (1) early (plantation) and late (reserve) successional forest ecosystems with a dense dicotyledonous plant herb layer, and (2) plantations with a dense grass herb layer and forests with a dense canopy closure (fruiting monoculture). Redundancy analysis confirmed separate habitat preferences of the three eudominant species. Generalised linear model indicated increasing preference of field vole for plantations with dominance of grass and <10–15 % admixed dicotyledonous plants while decreasing preference at ratios >10–15 %, and increasing preference of bank vole for plantations with a dicotyledonous plant ratio of >10–15 %. The biotopes monitored proved suitable for long-term survival of the dominant SM species. Early successional plantations and forest reserves also represent important refuges for a number of rarer SM species presently under threat.     

福建雄江黄楮林自然保护区两栖动物研究

采用样线调查法,对福建雄江黄楮林自然保护区两栖动物资源及其地理区系进行调查分析。结果表明,两栖动物有2目7科30种,保护区两栖动物资源种类丰富,种群数量多,具有很高的保护价值;本区两栖动物地理区划属于东洋界华中区的东部丘陵平原亚区闽北山区丘陵地理省,华中向华南区系过渡性质明显,与台湾两栖动物关系密切,是戴云山脉两栖动物的重要组成。     

Carabid species responses to hybrid poplar plantations in floodplains in France

Hybrid poplar plantations have become an important component of forest and agricultural landscapes in alluvial floodplains since poplars are among the fastest-growing trees in temperate regions. However, these habitats are thought to decrease biodiversity, including ground beetle diversity, as compared to other traditional land-uses such as grasslands and semi-natural forests. To evaluate the impacts of poplar plantations on carabid diversity, we tested whether carabid assemblages are more affected by land-use type than by canopy cover type in three alluvial floodplains in North-Eastern France. We stratified our 63-plot sampling design according to four habitat types based on land-use and plantation age. Non-metric multidimensional scaling revealed a successional gradient in species composition related to canopy cover progressing from grasslands through young, then adult poplar plantations, to semi-natural forests. Species-level response models showed that many carabid species distinguished the open habitats (grasslands and young poplar plantations) from the closed ones (adult poplar plantations and semi-natural forests). Only a few species preferred one of the traditional land-uses such as grasslands or semi-natural forests. Based on our data, the deleterious effect of poplar plantations on the conservation of ground beetles may not be as high as expected.     

都庞岭两栖动物生态学调查及多样性分析

1997年7月～8月,对湖南都庞岭国家级自然保护区进行了生物资源综合考察.结果表明该区有两栖动物2目8科12属31种.除3种古北界种类外,其余28种均为东洋种,占总种类的90.32%;东洋种中有13种主要分布于华中区,有11种为华中区和华南区共有种;国家二级保护动物有大鲵和虎纹蛙2种;尾斑瘰螈和中国瘰螈在湖南省主要分布于都庞岭山系;数量优势种有棘侧蛙、华南湍蛙、崇安湍蛙、花臭蛙、泽陆蛙、黑斑侧褶蛙、饰纹姬蛙等;香农-维纳多样性系数为1.3123,均匀度系数为0.9068.最后,对区系特征、资源状况和生态类型进行了分析,并提出了保护对策.     

Amphibian distributions in riparian and upslope areas and their habitat associations on managed forest landscapes in the Oregon Coast Range

Over the past 50 years, forested landscapes of the Pacific Northwest have become increasingly patchy, dominated by early successional forests. Several amphibian species associated with forested headwater systems have emerged as management concerns, especially after clearcutting. Given that headwater streams comprise a large portion of the length of flowing waterways in western Oregon forests, there is a need to better understand how forest management affects headwater forest taxa and their habitats. Mitigation strategies include alternatives to clearcutting, such as harvests that remove only part of the canopy and maintenance of riparian buffer strips. Our study investigates effects of upland forest thinning coupled with riparian buffer treatments on riparian and upland headwater forest amphibians, habitat attributes, and species-habitat associations. Amphibian captures and habitat variables were examined 5–6 years post-thinning within forest stands subject to streamside-retention buffers and variable-width buffers, as well as unthinned reference stands. We found no treatments effects, however, our results suggest that ground surface conditions (e.g., amount of rocky or fine substrate) play a role in determining the response of riparian and upland amphibians to forest thinning along headwater streams. Distance from stream was associated with amphibian abundance, hence retention of riparian buffers is likely important in maintaining microclimates and microhabitats needed for amphibians and other taxa. Moderate thinning and preservation of conditions in riparian and nearby upland areas by way of variable-width and streamside-retention buffers may be sufficient to maintain suitable habitat and microclimatic conditions vital to amphibian assemblages in managed headwater forests.     

Conservation of forest biodiversity and ecosystem properties in a pastoral landscape of the Ecuadorian Andes

High Andean cloud forests are home to a diversity of unique wildlife and are important providers of ecosystem services to people in the Andean regions. The extent of these cloud forests has been widely reduced through conversion to pasture for livestock, which threatens the forests’ ability to support biodiversity and provide ecosystem services. This paper explores whether impacts on woody plant biodiversity and four ecosystem properties (woody plant species richness, juvenile timber tree abundance, soil organic matter content and soil moisture) from converting forest to pasture can be mitigated if some woody forest vegetation is maintained within pastures. Woody vegetation in pastures was found to conserve those woody plant species that are more tolerant to exposure and grazing, but conservation of the high montane cloud forest community required areas of forest from which livestock were restricted. The sampled sites clustered according to woody plant species cover; these clusters represented a gradient from pasture with patches of shrubs to mature forest. Clusters differed in both woody plant species richness and number of juvenile timber trees whereas soil organic matter and soil moisture were observed to be similar among all clusters. This suggests that the different habitats may have some equivalent ecosystem properties. We conclude that the presence of woody vegetation in pastures may reduce some of the impacts of converting forest to pasture, but should not be considered a substitute for protecting large areas of forest, which are essential for maintaining woody plant species diversity in high Andean cloud forest.     

Bird communities in tropical agroforestry ecosystems: an underappreciated conservation resource

Tropical conservation and research focus primarily on protected areas and often ignore conservation values of surrounding agricultural lands. Understanding how species utilize agricultural land will maximize conservation efforts. We compared bird community composition in four habitats in northeastern Costa Rica: shade-grown cacao, live fences, riparian forest buffers, and preserved late-successional rainforest. Point counts over 2 months found 167 species from 36 families. Rainforest contained the most species unique to a habitat although richness per point was lower than in agricultural habitats. Half, 31, of the rainforest species did not occur in other habitats, while 106 species, mostly those preferring open areas, occurred in agroforest habitats but not rainforest. While agricultural habitats had fairly similar species composition to each other as determined by distance in an ordination, each also contained significant numbers, 9–30, of unique species. While intact rainforest remains central to conservation of tropical birds, agricultural lands with substantial trees, e.g., live fences, riparian buffers, and plantations with shade trees, can support a high richness of birds. These avian communities are not simply subsets of the rainforest species but include substantial numbers of unique species. Conservation contributions of these lands to species richness and complexity should be considered in conservation, and trees in these habitats preserved.