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991.
Erick M. G. Cordeiro James F. Campbell Thomas W. Phillips Kimberly A. With 《Landscape Ecology》2018,33(11):1881-1894
Context
Although animal movement behaviors are influenced by spatial heterogeneity, such behaviors can also generate spatial heterogeneity via interactions with the emergent spatial structure and other individuals (i.e., the social landscape).Objective
Elucidate the behavioral and ecological mechanisms of pattern formation in a homogeneous resource landscape.Methods
We analyzed the movement pathways and space-use patterns of the lesser grain borer (Rhyzopertha dominica) within homogeneous resource landscapes (wheat kernels). Experimental trials consisted of individual beetles foraging alone or paired with a member of the same or different sex.Results
We identified two sources of pattern formation: (1) beetles were attracted to areas where they or another beetle had previously fed, leading to increased patchiness via positive reinforcement; and (2) the presence of conspecifics affected whether and at what scales patchiness occurred. Solitary males had lower rates of movement and less tortuous pathways than solitary females, but both sexes generated fine-scale patchiness in the resource distribution. Patchy resource landscapes were also generated by male–female pairs, but not by same-sex pairings. Paired females in particular exhibited significantly greater daily net displacements and more random space use than solitary females.Conclusions
Pattern formation is a complex process, even in a relatively simple, homogeneous resource landscape. In particular, patterns created by individuals when foraging alone versus in pairs underscores how social interactions can fundamentally alter the resultant pattern of heterogeneity that emerges in resource landscapes.992.
Riana Gardiner Glen Bain Rowena Hamer Menna E. Jones Christopher N. Johnson 《Landscape Ecology》2018,33(11):1837-1849
Context
The classical theory of island biogeography explains loss of species in fragmented landscapes as an effect of remnant patch size and isolation. Recently this has been challenged by the habitat amount and habitat continuum hypotheses, according to which persistence in modified landscapes is related to total habitat amount rather than habitat configuration or the ability of species to use all habitats to varying degrees. Distinguishing between these theories is essential for effective conservation planning in modified landscapes.Objective
Identify which factors of habitat type, amount and configuration predict the persistence of a keystone woodland specialist, the eastern bettong Bettongia gaimardi, in a fragmented landscape.Method
In the Midlands region of Tasmania we carried out camera surveys at 62 sites in summer and winter. We included habitat and landscape features to model whether habitat amount or patch size and isolation influenced the presence of the eastern bettong, and to measure effects of habitat quality.Results
Habitat amount within a 1 km buffer was a better predictor of occupancy than patch size and isolation. Occupancy was also affected by habitat quality, indicated by density of regenerating stems.Conclusion
Our results support the habitat amount hypothesis as a better predictor of presence. For a species that is able to cross the matrix between remnant patches and utilise multiple patches, the island biogeography concept does not explain habitat use in fragmented landscapes. Our results emphasize the value of small remnant patches for conservation of the eastern bettong, provided those patches are in good condition.993.
Context
Recent research suggests that novel geodiversity data on landforms, hydrology and surface materials can improve biodiversity models at the landscape scale by quantifying abiotic variability more effectively than commonly used measures of spatial heterogeneity. However, few studies consider whether these variables can account for, and improve our understanding of, species’ distributions.Objectives
Assess the role of geodiversity components as macro-scale controls of plant species’ distributions in a montane landscape.Methods
We used an innovative approach to quantifying a landscape, creating an ecologically meaningful geodiversity dataset that accounted for hydrology, morphometry (landforms derived from geomorphometric techniques), and soil parent material (data from expert sources). We compared models with geodiversity to those just using topographic metrics (e.g. slope and elevation) and climate data. Species distribution models (SDMs) were produced for ‘rare’ (N?=?76) and ‘common’ (N?=?505) plant species at 1 km2 resolution for the Cairngorms National Park, Scotland.Results
The addition of automatically produced landform geodiversity data and hydrological features to a basic SDM (climate, elevation, and slope) resulted in a significant improvement in model fit across all common species’ distribution models. Adding further geodiversity data on surface materials resulted in a less consistent statistical improvement, but added considerable conceptual value to many individual rare and common SDMs.Conclusions
The geodiversity data used here helped us capture the abiotic environment’s heterogeneity and allowed for explicit links between the geophysical landscape and species’ ecology. It is encouraging that relatively simple and easily produced geodiversity data have the potential to improve SDMs. Our findings have important implications for applied conservation and support the need to consider geodiversity in management.994.
Javier Babí Almenar Benedetto Rugani Davide Geneletti Tim Brewer 《Landscape Ecology》2018,33(12):2047-2059
Context
The study of ecosystem services has extended its influence into spatial planning and landscape ecology, the integration of which can offer an opportunity to enhance the saliency, credibility, and legitimacy of landscape ecology in spatial planning issues.Objectives
This paper presents a conceptual framework suitable for spatial planning in human dominated environments supported by landscape ecological thinking. It seeks to facilitate the integration of ecosystem services into current practice, including landscape metrics as suitable indicators.Methods
A literature review supported the revision of existing open questions pertaining to ecosystem services as well as their integration into landscape ecology and spatial planning. A posterior reflection of the current state-of-the-art was then used as a basis for developing the spatial planning conceptual framework.Results and conclusion
The framework is articulated around four phases (characterisation, assessment, design, and monitoring) and three concepts (character, service, and value). It advocates integration of public participation, consideration of “landscape services”, the inclusion of ecosystem disservices, and the use of landscape metrics for qualitative assessment of services. As a result, the framework looks to enhance spatial planning practice by providing: (i) a better consideration of landscape configuration in the supply of services (ii) the integration of anthropogenic services with ecosystem services; (iii) the consideration of costs derived from ecosystems (e.g. disservices); and (iv) an aid to the understanding of ecosystem services terminology for spatial planning professionals and decision makers.995.
Context
Forest cover change analyses have revealed net forest gain in many tropical regions. While most analyses have focused solely on forest cover, trees outside forests are vital components of landscape integrity. Quantifying regional-scale patterns of tree cover change, including non-forest trees, could benefit forest and landscape restoration (FLR) efforts.Objectives
We analyzed tree cover change in Southwestern Panama to quantify: (1) patterns of change from 1998 to 2014, (2) differences in rates of change between forest and non-forest classes, and (3) the relative importance of social-ecological predictors of tree cover change between classes.Methods
We digitized tree cover classes, including dispersed trees, live fences, riparian forest, and forest, in very high resolution images from 1998 to 2014. We then applied hurdle models to relate social-ecological predictors to the probability and amount of tree cover gain.Results
All tree cover classes increased in extent, but gains were highly variable between classes. Non-forest tree cover accounted for 21% of tree cover gains, while riparian trees constituted 31% of forest cover gains. Drivers of tree cover change varied widely between classes, with opposite impacts of some social-ecological predictors on non-forest and forest cover.Conclusions
We demonstrate that key drivers of forest cover change, including topography, road distance and historical forest cover, do not explain rates of non-forest tree cover change. Consequently, predictions from medium-resolution forest cover change analyses may not apply to finer-scale patterns of tree cover. We highlight the opportunity for FLR projects to target tree cover classes adapted to local social and ecological conditions.996.
Context
In agricultural landscapes, riparian forests are used as a management tool to protect stream ecosystems from agricultural activities. However, the ability of managers to target stream protection actions is limited by incomplete knowledge of scale-specific effects of agriculture in riparian corridor and catchment areas.Objectives
We evaluated scale-specific effects of agricultural cover in riparian corridor and catchment areas on stream benthic macroinvertebrate (BMI) communities to develop cover targets for agricultural landscapes.Methods
Sixty-eight streams assigned to three experimental treatments (Forested Riparian, Agricultural Riparian, Agricultural Catchment) were sampled for BMIs. Ordination and segmented regression were used to assess impacts of agriculture on BMI communities and detect thresholds for BMI community metrics.Results
BMI communities were not associated with catchment agricultural cover where the riparian corridor was forested, but were associated with variation in catchment agriculture where riparian forests had been converted to agriculture. Trait-based metrics showed threshold responses at greater than 70% agricultural cover in the catchment. Increasing agriculture in the riparian corridor was associated with less diverse and more tolerant BMI communities. Eight metrics exhibited threshold responses ranging from 45 to 75% agriculture in the riparian corridor.Conclusions
Riparian forest effectively buffered streams from agricultural activity even where catchment agriculture exceeds 80%. We recommend managers prioritize protection of forested riparian corridors and that restore riparian corridors where agricultural cover is near identified thresholds be a secondary priority. Adoption of catchment management actions should be effective where the riparian corridor has been converted to agriculture.997.
Global warming, altering the physiology and irrigation demand of grapevines, has already been perceived in certain premium viticulture regions across the world. Selection of proper rootstocks for especially new cultivars has vital role for a sustainable viticulture under water-deficit conditions. The grapevine cultivar ‘Michele Palieri’ has been finding a good reception on the global markets. The objective of this study was to determine the response of ‘Michele Palieri’ cultivar to deficit irrigation using different rootstocks with distinct genetic origins. Two irrigation regimes (Full Irrigation [FI] and Deficit Irrigation [DI]) were applied to the vines of different grafting combinations of ‘Michele Palieri’ with Kober 5 BB, Richter 99, Richter 110, 140 Ruggeri, 44–53 Malégue or grown on own roots. Two years old vines were cultivated in 60?L pots containing sterile peat under controlled glasshouse conditions. Irrigations were regulated according to soil water matric potential (Ψm) levels using tensiometers. The volume of the irrigation water that has to be applied to attain 100% field capacity was performed as FI, while 50% of FI was considered as DI. The water was transported directly into the pots by micro-irrigation systems consisting of individual spaghetti tubes. The vines of DI treatment showed visible symptoms of mild water stress (e.?g., loss of turgor in shoot tips), but no defoliation or leaf necrosis occurred. DI treatment reduced the gs of ‘Michele Palieri’ scion cultivar in varying levels depending on the rootstock. DI treatment also affected vegetative growth of the scion cultivar in different levels. For example, the greatest decrease (26.7%) in shoot length resulting from DI was determined in ‘Michele Palieri’/5 BB grapevines, followed by own rooted vines (13.1%), while the lowest change (2.4%) was found in vines grafted on 110?R. Overall findings of this study imply that the rootstocks originating from V. berlandiery?×?V. rupestris hybrids (110?R, 99?R, 140?Ru and 44–53?M) better performed in a similar genetic aptitude under deficit irrigation regime while the rootstock 5 BB (V. berlandiery?×?V. rupestris) showed more susceptible responses. On the other hand, the general response of own rooted vines were better than those grafted on 5 BB. Therefore, the use of one of V. berlandiery?×?V. rupestris hybrids may be a better choice for viticulture under semiarid regions. 相似文献
998.
999.
In this study, energy use patterns and the functional relationship between energy inputs and output for pomegranate production were investigated in Antalya province in Turkey. It further objective to identify greenhouse gas (GHG) emissions in pomegranate production. Data were obtained from 75 farms using face-to-face interview method. The results indicated that 50,605.5?MJ ? ha?1 of total energy input was required for 76,252.3?MG ? ha?1 pomegranate energy output. 1.51 unit energy output was provided by using 1 unit energy input. 1 unit energy output and 1?kg pomegranate require 0.66 unit and 2.57?MJ energy input, respectively. The average CO2 emission amounts were also calculated to be 1.73?t CO2 per hectare and 88.1?kg CO2 per 1000?kg pomegranate production. Electricity, fertilizers and pesticides were the highest contributors to GHG emissions. Both total energy input usage and GHG emission amounts have been found to be decreasing as the farm size increases. Increasing scale of pomegranates orchards will not only increase energy efficiency and productivity but also decrease environmental pollution and damages. The regression analysis revealed that, excessive use of machinery and fuel inputs results in a decline in energy production in pomegranate. 相似文献
1000.
Some of the advantages of soilless production systems over conventional systems are higher yield, better pest control management and more efficient labor use. Among berries, strawberry responds quite well to soilless production systems. Major yield-affecting factors for strawberries in soilless systems may be listed as; growing medium, source and types of plantlets, density of plants and efficiency of fertigation system. The present research was conducted with strawberry plants (Fragaria x ananassa ‘Camarosa’) grown in four different media; (1) Cocopeat (C), (2) Peat (P) and (3 and 4) 1:1 mixtures with Pumice (Pu), to evaluate the effects of soilless media on marketable yield and root-shoot morpho-physiological parameters. Correlation measurements were made to assess if there is any interaction between yield and any tested morpho-physiological feature. The experiment was conducted in greenhouse, using frigo plantlets (11.6 plantlet/m2) planted in July and through 1 June of following year. Results showed that growth medium had an effect on yield, numbers of developed leaves, shoot-root dry mass, number and length of roots. Yield was correlated with these morphological features. Growth medium also had an influence on plant nutrient accumulations i.?e., shoot accumulation of nitrogen (N) and potassium (K) and root accumulation of phosphorus (P) and all the micro-nutrients that with exception of boron (B). There were some interactions between yield and plant nutrient content of tissues determined by correlation analyses. The most striking were negative correlations with yield and shoot N–K amounts and positive correlation with yield and root P amount. Some positive correlations were also found between yield and copper (Cu), manganese (Mn) and zinc (Zn) contents of both shoot and root tissues. Boron (B) contents was correlated only with the root tissues. The medium which had the best overall performance for soilless strawberry production was C?+?Pu and should be recommended to be used with frigo plantlets of ‘Camarosa’. 相似文献