<Emphasis Type="Italic">Cabruca</Emphasis> agroforests in southern Bahia,Brazil: tree component,management practices and tree species conservation

In southern Bahia, Brazil, cabrucas are the traditional agroforests in which cacao trees are planted under thinned-out native forests. To analyze the role of cabrucas in tree species conservation, we inventoried the non-cocoa trees in 1.0 ha plots of cabruca in 16 cocoa farms and compared our results with a similar survey undertaken in the early 1960s in the same region to analyze the long term changes. We also interviewed 160 cocoa farmers to investigate their preferences for species and the main practices used in managing shade trees. The cabrucas showed high levels of tree diversity for an agroforestry system (Shannon index ranging from 2.21 to 3.52) and also high variation in structure and composition among the different farms. Forest specialist trees accounted for most species (63.9%) in the survey and were among the species most preferred by the farmers, although we found evidence that some of these trees are gradually being replaced by other species. Our results indicate that cabrucas are poor substitutes for undisturbed forests in terms of tree species richness, but their presence in human-altered landscapes is of utmost importance to the conservation of forest tree species as they increase overall heterogeneity and may serve as ecological corridors, additional habitats, and buffer zones.     

Are coffee agroforestry systems suitable for circa situm conservation of indigenous trees? A case study from Central Kenya

Coffee agroforestry systems (CAFS) are often considered to be species-rich, potentially contributing to the conservation of indigenous trees. To investigate the conservation capacity of a Kenyan CAFS, all tree species on 62 smallholder coffee farms (covering 39 ha in total) in the Aberdare Mountains of Central Kenya were recorded. In total, 6,642 trees of 59 species were enumerated, with a mean density of 256 trees per ha and a mean species richness of 11.2 species per farm. Indigenous species represented 63 % of the richness but only 31 % of the abundance. For individual farms, as expected, farm size had a positive correlation with tree species richness, but more interestingly there was a negative correlation with tree density. Cluster analysis based on densities of the 18 most important species (defined by an importance value index) revealed two groups of farms: one cluster represented small farms (mean size = 0.4 ha) with high tree species diversity and individual density, particularly of indigenous trees; the other cluster represented large (mean size = 1 ha) and less diverse farms with low tree densities, particularly regarding indigenous species. Tree individuals were unevenly distributed within farms, being more frequent in living fences (38 % of all individuals), the garden zone (20 %) and in coffee plots (18 %). The relative occurrence of indigenous species was also uneven, being greater in living fences and the garden zone. Most adult trees (83 %) were planted, but only 46 % of seedlings were, revealing the active removal of volunteer seedlings by farmers as trees mature. Surveyed coffee farms harboured 20 % of the 135 tree species of the potential natural vegetation for the region, but only 3.6 % of the on-farm tree individuals belonged to the most valuable types of dominant and forest vegetation. Thus, although a source of significant tree cover and heterogeneity at landscape level, the value of these CAFS as circa situm reservoirs of forest tree species is questionable.     

Implications of shifts in coffee production on tree species richness, composition and structure on small farms around Mount Kenya

Small coffee farms around Mount Kenya in Kenya contain many planted and remnant tree species but little is known in the region about the relationship between trees on farms and the methods and dynamics of coffee production. Shifts in production may alter tree diversity and potentially impact on future biodiversity conservation efforts by affecting niches available for indigenous trees on farms. Here, knowledge was gathered on how changes in coffee production on 180 small farms around Mount Kenya may affect tree diversity, categorizing farms according to coffee yield levels over a period of five years as increasing, decreasing or stable production. Tree species richness, abundance and composition were analyzed using species accumulation curves, Rènyi diversity profiles, rank abundance and ecological distance ordinations, and the effects of coffee production examined using quasi-Poisson generalized linear regressions. Species richness were positively correlated with tree basal area but negatively related to coffee, banana and maize yields value. A difference in average tree species richness, abundance and basal area on increasing farms was observed compared to the decreasing and stable farms, even though formal tests on richness and densities differences were inconclusive. These dynamics do not significantly influence vegetation structure but seem to have a bearing on species composition on farms of different coffee production. The overall low abundance (23 % of trees) but high richness (78 % of species) of indigenous trees on coffee farms could change markedly if the dynamics observed in the current study persist, indicating the need for the development of intensified multi-species cropping systems.     

Variation in Indigenous Forest Resource Use in Central Guyana

Sustainable forest conservation strategies should be based on local as well as landscape-scale forest resource use data. Using ecological and sociological techniques, we test the hypotheses that (1) forest resource use differs between ethnic and socioeconomic indigenous groups and (2) that this difference results in differing spatial patterns of resource use, with implications for forest diversity and for conservation planning. In the North Rupununi Guyana, three adjacent indigenous communities (differing in their indigenous/immigrant balance) were recorded using 73 animal and 164 plant species (plus several unidentified ethno-species). Farm sites formed important foci for most forest based activities and ex-farm sites supported similar floristic diversity to surrounding forest. Resource usage differences between communities could be attributed to socio-cultural drivers, e.g. mammal meat consumption and the use of the fruits from the palm tree A. maripa were higher in more traditional households. When extracting household construction timber, lower income groups created small scattered felling sites akin to tree fall gaps whereas higher income groups created larger gaps. Lower income (indigenous) households tended to clear larger but more contained sites for farming while mixed or non-Amerindian household tended to clear smaller but more widely dispersed farm sites. These variations resulted in different patterns of forest disturbance originating from agriculture and timber extraction.     

Linking Trees on Farms with Biodiversity Conservation in Subsistence Farming Systems in Nepal

The Kingdom of Nepal extends 800 km east to west along the southern slopes of the Himalayas. Because of its biogeographical position, Nepal contains biological elements of both the Indo-Malayan and Palaearctic realms. Beside the trees in forest ecosystems, a large number of tree species are maintained on farms as part of subsistence farming systems. The role of these trees in ensuring the sustainability of agricultural production and the importance of traditional farming systems for the conservation of crop diversity have been well documented. However, the status of farm trees and their role in biodiversity conservation are poorly documented. This paper presents a case study of two villages in the western middle hills of Nepal. It highlights the role of traditional agroforestry practices for the conservation of tree diversity and argues that farms can be considered biodiversity reservoirs. Farm trees help to reduce pressure on community and government forests and create a favorable environment for many plant and animal species. Farm trees also provide social functions in that households with many farm trees no longer exercise their communal rights to extract grass products from community forests, which in turn benefits poor and disadvantaged households. The paper discusses possibilities to improve the role of farm trees in biodiversity conservation. It argues for the development of mechanisms such as tax exemptions and conservation credits that provide benefits to rural communities as compensation for their local and global environmental services including biodiversity conservation.     

Tree Biodiversity, Land Dynamics and Farmers’ Strategies on the Agricultural Frontier of Southwestern Burkina Faso

In the sub-humid part of Burkina Faso, population growth, migrations and new marketing opportunities have induced rapid land-use changes and social reorganization, leading to new approaches to natural resource management. The objective of this study was to evaluate tree biodiversity parameters in agroforestry parklands (scattered trees in crop land) as population increases and fallows become shorter. Out of about 100 tree species existing in the area, and 50 commonly found in traditional parklands, only 3 indigenous and 2 non-native species hold a significant importance for farmers, all for their fruits. No indigenous tree species are planted, but a few are protected when clearing the land. Planted cashew nut orchards develop rapidly and are seen as a land tenure guarantee and an important source of income. Given these facts, the perspectives for tree biodiversity management in farmers’ land may appear bleak. Yet, the importance given by farmers to specific tree products demonstrates that trees do play a part in land development and farmers’ strategies. Existing practices of farmers show potential for improved land-use and spatial patterning of the land, as revealed by emerging parklands and orchards. Our data do not confirm common statements that migrant farmers do not manage the land as sustainably as native farmers do. Rather than trying to conserve tree biodiversity as it is, researchers and developers should identify with farmers the complementarities between trees and farms and promote tree biodiversity through existing practices.     

Origins and genetic conservation of tropical trees in agroforestry systems: a case study from the Peruvian Amazon

Hundreds of native tree species are currently found in extensive agroforestry ecosystems in the Peruvian Amazon, forming an important reservoir of biodiversity. To further promote conservation, farmers are encouraged to supplement intra-specific genetic diversity in these populations with seed collected from local forests. For some tree species, however, this approach may be inappropriate, as stands of these taxa already found on-farm may not be of local origin. Despite this issue being of importance for conservation, little information is available on the history of cultivated trees in the region, a situation that we here rectify for the important fruit tree Inga edulis. Based on nuclear SSR and chloroplast DHPLC analyses of closely geographically matched natural and planted stands at five sites, it appears that cultivated material of I. edulis is primarily of non-local origin, indicating that conservation based on new wide-scale infusions from local wild stands into farms may be inappropriate in the region. Although nuclear and chloroplast diversity were both lower in planted stands, values were still relatively high (∼80 and 70% of natural stands, respectively), indicating that when farmers plant trees, good collection practice of seed from already cultivated I. edulis should be an effective means for ensuring long-term conservation on farms.     

The role of farm structure on bird assemblages around a Kenyan tropical rainforest

Although it is clear that the farmlands neighbouring fragmented forests are utilized by some forest birds, it is not clear how birds in general respond to farmland habitat mosaic. An effort was made to determine how bird density and foraging assemblages were influenced by farm structural characteristics and distance from forest edge. Thirty farms up to a distance of 12 km around Kakamega forest in western Kenya were studied. Farm structure entailed size, hedge volume, habitat heterogeneity, woody plant density, plant diversity and crop cover. Birds were surveyed using line transects and DISTANCE analyses and classified into six feeding guilds and three habitat associations. Size of farms increased away from the forest, as woody plant density, plant diversity, indigenous trees and subsistence crop cover declined. The most important farm structure variable was hedge volume, which enhanced bird species richness, richness of shrub‐land bird species and insectivorous bird density (R = 0.58, P < 0.01). Bird density increased with tree density while indigenous trees were suitable for insectivores and nectarivores. There were very few forest bird encounters. Agricultural practices incorporating maintenance of hedges and sound selection of agroforestry trees can enhance conservation of birds on farmland, though, not significantly for forest species.     

Litter-dwelling ants as bioindicators to gauge the sustainability of small arboreal monocultures embedded in the Amazonian rainforest

One of the greatest threats to biodiversity and the sustainable functioning of ecosystems is the clearing of forests for agriculture. Because litter-dwelling ants are very good bioindicators of man-made disturbance, we used them to compare monospecific plantations of acacia trees, cocoa trees, rubber trees and pine trees with the surrounding Neotropical rainforest (in contrast to previous studies on forest fragments embedded in industrial monocultures). Although the global level of species turnover was weak, species richness decreased along a gradient from the forest (including a treefall gap) to the tree plantations among which the highest number of species was noted for the cocoa trees, which are known to be a good compromise between agriculture and conservation. Species composition was significantly different between natural habitats and the plantations that, in turn, were different from each other. Compared to the forest, alterations in the ant communities were (1) highest for the acacia and rubber trees, (2) intermediate for the cocoa trees, and, (3) surprisingly, far lower for the pine trees, likely due to very abundant litter. Functional traits only separated the rubber tree plantation from the other habitats due to the higher presence of exotic and leaf-cutting ants. This study shows that small monospecific stands are likely sustainable when embedded in the rainforest and that environmentally-friendly strategies can be planned accordingly.     

Diversity of plants in cocoa agroforests in the humid forest zone of Southern Cameroon

In the humid forest zone of Southern Cameroon, farmers generally associate cocoa with native and exotic trees in complex agroforestry systems. Despite the socio-economic and ecological importance of these systems, few studies have investigated their plant composition. We investigated tree composition of cocoa agroforests along a gradient of market access, population density and resource use intensity in the humid forest zone of southern Cameroon, comprising (i) the sub-region of Yaoundé, (ii) the sub-region of Mbalmayo, and (iii) the sub-region of Ebolowa. Market access, population density and resource use intensity all decreased from the first to the third sub-region. We quantified the diversity of tree species associated with cocoa within individual agroforests, among agroforests in the same region, and among the three sub-regions, and classified the tree species according to their main uses. A total of 9.1 ha belonging to 60 cocoa agroforests were inventoried in 12 villages. We encountered a total of 206 tree species with an average of 21 tree species per agroforest. In the more urbanized area around Yaoundé, agroforests were less diverse than in the other sub-regions. In all of the agroforests, food producing tree species tended to be more frequent than other species. Two thirds of the food trees were native forest species and one third was introduced. From Ebolowa to Yaoundé, the density of food producing trees doubled and the density of exotic food-producing species increased relative to native species. Some local species producing high-value non-timber forest products were found in the agroforests, but their density was far lower than that of exotic tree species. The agroforests also provide medicine, charcoal and other products for household consumption and sale. We conclude that unless there are specific efforts to promote local forest tree species in cocoa agroforests, these will progressively lose importance with increasing market access, population pressure and land use intensity.     

The ant mosaic on cocoa and other tree crops in Western Nigeria

Abstract. 1. Data on ant distribution on the various blocks of cocoa studied at Gambari Experimental Station shows a clear mosaic of ant colonies. Distribution maps and analyses of associations between common species are given.
2. Surveys of ant populations on kola, cashew, coffee, oil palm, plantain and indigenous forest trees revealed dominance by the same ant species as occur on cocoa.
3. The adundance of any particular dominant ant species is shown to be related mainly to the habitat provided by a specific tree crop.
4. The potential utilization of ants as biological control agents is discussed.     

Plant biodiversity and vegetation structure in traditional cocoa forest gardens in southern Cameroon under different management

Floristic surveys were performed in 17 traditional cocoa forest gardens under different management regimes in the humid forest area of southern Cameroon, to assess the impact of intensification on plant biodiversity. This impact was evaluated by analyzing species richness, vegetation structure, carbon sequestration and above ground biomass. We hypothesize that: (a) plant (tree and herbs) species richness is negatively correlated to management intensity and (b) vegetational density predictably change with management intensity. Our results show that management as practiced in traditional cocoa forest gardens in southern Cameroon following a gradient of intensification from extensive cocoa forest gardens with high floristic diversity to intensive ones strongly impacts plant diversity, plant biomass and to some extend carbon storage with possible negative consequences on biodiversity. Great differences in species richness, species composition, and, for trees, diameter at breast height and basal area were evident among the five types of traditional cocoa forest garden systems investigated. In terms of plant species richness, we found a decreasing gradient of plant species numbers from extensive forest gardens to intensive ones. This study also highlights the importance of the Management Index for quantifying differences in the management; this index could be used to standardize certification procedures and assess conservation progress and success. Our findings support the idea that traditional cocoa forest gardens can help to protect many forest species, sustains smallholder production and offer more scope for conservation of biodiversity, at both species-level and landscape-level. Moreover, diverse traditional cocoa forest gardens may help in regulating pests and diseases and allow for efficient adaptation to changing socioeconomic conditions.     

Managing genetic variation in tropical trees: linking knowledge with action in agroforestry ecosystems for improved conservation and enhanced livelihoods

Tree species in agroforestry ecosystems contribute to the livelihoods of rural communities and play an important role in the conservation of biodiversity. Unless agroforestry landscapes are productive, however, farmers will not maintain or enhance the range and quality of tree species in them, and both income opportunities and biodiversity will be lost. Productivity depends on both tree species diversity and genetic (intra-specific) variation, but research on the latter has until recently not received the recognition it deserves. Worse, when knowledge on tree genetic variation in agroforestry systems has become available, it has not generally been linked in any systematic way with management, indicating a disjunction between research and field-level practice. In this essay, we attempt to bridge this gap by considering three questions: why is genetic diversity important in tree species? What is our current state of knowledge about intra-specific variation in trees in agroforestry systems? And, finally, what practical interventions are possible to support the conservation of this diversity in agricultural landscapes, while enhancing farmers’ livelihoods? A wide genetic base in agroforestry trees is essential to prevent inbreeding depression and allow adaptation to changing environmental conditions and to altering markets for tree products. Recent evidence shows, however, that many species are subject to poor germplasm collection practice, occur at low densities in farmland, and are found in highly aggregated distributions, all of which observations raise concerns about productivity and sustainability. A range of germplasm-access based interventions is necessary to improve current management, including the enhancement of community seed- and seedling-exchange networks, and the development of locally based tree domestication activities. Equally necessary, but more difficult to address, is the development of markets that support genetic diversity in tropical tree species; we discuss approaches by which this may be undertaken.     

Conservation value of degraded habitats for forest birds in southern Peninsular Malaysia

Clearance of tropical forest for agricultural purposes is generally assumed to seriously threaten the survival of forest species. In this study, we quantified the conservation value, for forest bird species, of three degraded habitat types in Peninsular Malaysia, namely rubber tree plantations, oil palm plantations, and open areas. We surveyed these degraded habitats using point counts to estimate their forest bird species richness and abundance. We assessed whether richness, abundance, and activities of different avian dietary groups (i.e. insectivores and frugivores) varied among the habitats. We identified the critical habitat elements that accounted for the distribution of forest avifauna in these degraded habitats. Our results showed that these habitats harboured a moderate fraction of forest avifauna (approximately 46–76 species) and their functions were complementary (i.e. rubber tree plantations for moving; open habitats for perching; shrubs in oil palm plantations for foraging). In terms of species richness and abundance, rubber tree plantations were more important than oil palm plantations and open habitats. The relatively high species richness of this agricultural landscape was partly due to the contiguity of our study areas with extensive forest areas. Forecasts of forest-species presence under various canopy cover scenarios suggest that leaving isolated trees among non-arboreal crops could greatly attract relatively tolerant species that require tree canopy. The conservation value of degraded habitats in agricultural landscapes seems to depend on factors such as the type of crops planted and distance to primary forest remnants.     

Bird diversity in cacao farms and forest fragments of western Panama

Theobroma cacao plantings, when managed under the shade of rainforest trees, provide habitat for many resident and migratory bird species. We compared the bird diversity and community structure in organic cacao farms and nearby forest fragments throughout mainland Bocas del Toro, Panama. We used this dataset to ask the following questions: (1) How do bird communities using cacao habitat compare to communities of nearby forest fragments? (2) To what extent do Northern migratory birds use shaded cacao farms, and do communities of resident birds shift their abundances in cacao farms seasonally? (3) Do small scale changes in shade management of cacao farms affect bird diversity? Using fixed radius point counts and additional observations, we recorded 234 landbird species, with 102 species that were observed in both cacao and forest fragments, 86 species that were only observed in cacao farms, and 46 species that were restricted to forest fragments. Cacao farms were rich in canopy and edge species such as tanagers, flycatchers and migratory warblers, but understory insectivores were nearly absent from cacao farms. We observed 27 migratory species, with 18 species in cacao farms only, two species in forest only, and seven species that occurred in both habitats. In cacao farms, the diversity of birds was significantly greater where there was less intensive management of the canopy shade trees. Shade tree species richness was most important for explaining variance in bird diversity. Our study shows that shaded cacao farms in western Panama provide habitat for a wide variety of resident and migratory bird species. Considering current land use trends in the region, we suggest that action must be taken to prevent conversion away from shaded cacao farms to land uses with lower biodiversity conservation value.     

Biodiversity conservation,yield, and alternative products in coffee agroecosystems in Sumatra,Indonesia

Agroecology and conservation must overlap to protect biodiversity and farmer livelihoods. Coffee agroecosystems with complex shade canopies protect biodiversity. Yet, few have examined biodiversity in coffee agroecosystems in Asia relative to the Americas and many question whether coffee agroecosystems can play a similar role for conservation. We examined vegetation, ant and bird diversity, coffee yields and revenues, and harvest of alternative products in coffee farms and forests in SW Sumatra, Indonesia near Bukit Barisan Selatan National Park (BBS). BBS is among the last habitats for large mammals in Sumatra and >15,000 families illegally cultivate coffee inside of BBS. As a basis for informing management recommendations, we compared the conservation potential and economic outputs from farms inside and outside of BBS. Forests had higher canopy cover, canopy depth, tree height, epiphyte loads, and more emergent trees than coffee farms. Coffee farms inside BBS had more epiphytes and trees and fewer coffee plants than farms outside BBS. Tree, ant, and bird richness was significantly greater in forests than in coffee farms, and richness did not differ in coffee farms inside and outside of BBS. Species similarity of forest and coffee trees, ants, and birds was generally low (<50%). Surprisingly, farms inside the park were significantly older, but farm size, coffee yields, and revenues from coffee did not depend on farm location. Farmers outside BBS received higher prices for their coffee and also more often produced other crops in their coffee fields such that incentives could be created to draw illegal farmers out of the park. We also discuss these results with reference to similar work in Chiapas, Mexico to compare the relative contribution of coffee fields to conservation in the two continents, and discuss implications for working with farmers in Sumatra towards conservation plans incorporating sustainable coffee production.     

Long-term impacts of grazing on indigenous forest remnants on North Island hill country, New Zealand

Small isolated patches of native forest surrounded by extensive pastoral grasslands, characteristic of many New Zealand rural landscapes, represent an important reservoir of lowland biodiversity. Improved management of them is a major focus of biodiversity conservation initiatives in New Zealand. We quantified the long-term impacts of grazing on indigenous forest remnants in hill country at Whatawhata, western Waikato, North Island. Structure and composition were compared between forest fragments grazed for >50 years and nearby ungrazed continuous forest. Grazed fragments had shorter and less shady canopies, sparser understoreys, tree populations with larger mean diameters, and ground layers with lower cover of litter and higher cover of vegetation and bare soil than continuous forest. Fragments also had lower indigenous-plant species richness, especially in sapling and seedling populations, and almost no palatable indigenous shrubs, terrestrial orchids, and ferns that require high humidity (e.g. Hymenophyllum spp.), but contained many indigenous and adventive herbaceous species. A transition appears to be occurring in grazed fragments from tall, long-lived trees like Beilschmiedia tawa and Dysoxylum spectabile to short and shorter-lived trees like Kunzea ericoides, Melicytus ramiflorus, and Dicksonia squarrosa. Because grazing inhibits most regeneration processes, unfenced remnants of conifer–broadleaved forest are unlikely to be maintained in grazed pasture in the long term.     

Using suitable projects in adding value to nonwood forest products in The Philippines: The Copal (Agathis Philippinensis) trade in Palawan

Using Suitable Projects in Adding Value to Nonwood Forest Products in the Philippines: The Copal (Agathis philippinensis)Trade in Palawan. Economic Botany 58(3):476-485, 2004. The Philippines is a country that has little low-forest cover left, but it still has many useful forest species. Despite the decline of forest area and the degradation of forests, many of the poorest households, both indigenous and migrant, are pushed into the remaining forest area and depend on forest goods for their subsistence and monetary income. These goods are inevitably nonwood forest products (NWFPs) because timber extraction is now illegal in many parts of the country. The extraction of nonwood forest products, such as resin and rattan, is the only source of a cash income for many households. However, despite the long tradition of NWFP extraction in forest-edge villages, the income that collectors get from these products is still minimal. The impediments to a more equitable and efficient trade in NWFPs are examined, and possible ways of adding value locally to NWFPs are presented, using almaciga (Agathis philippinensis) resin extraction as a case study.     

Conservation and human livelihoods at the crossroads: Local needs and knowledge in the management of Arabuko Sokoke Forest

Arabuko Sokoke Forest is the largest remaining single block of indigenous dry coastal tropical forest in Eastern Africa. Households within a 5 km buffer zone depend heavily on the forest for their livelihood needs, and the pressure on forest resources is on the increase. In May 2015, 109 households were interviewed on resources they obtain from the forest, in terms of the self‐reported level of monthly income. We found household income and farm size significantly positively correlated with benefits from the forest, highlighting the possible influence of household wealth in exploiting forest resources. A large proportion of households (32%) had limited knowledge of local birds, while human–bird conflict was reported by 44% of the households. While many households were keen to participate in conservation projects that maintain the forest, 44% had no knowledge of the forest management plan, and 60% of those interviewed had no idea of how forest zones were designated for particular activities. Drivers for local community participation in conservation projects appear to be sustainable income and fulfilment of basic household needs.     

西双版纳榕树的民族植物文化

榕树是桑科榕属（ＦｉｃｕｓＬ．）乔木种类的总称,在西双版纳热带森林中有４８种（不包括变种）,是一个物种最多、种群较大的类群,与生活在森林中的各族人民有密切的关系,形成了独特的民族榕树文化。西双版纳各民族利用多种榕树的嫩枝叶、果子作蔬菜和水果,利用多种榕树治疗疾病,一些种类被当地民族视为“神（龙）树”和“佛树”,各族人民还在村寨附近、寺庙庭院和家庭庭园中栽培多种榕树,既供日常生活之需,又改善村社的生态环境。它不仅关系到自然生态系统的平衡,而且对人与自然的协调发展有重要意义