Landscape and Ecological Engineering最新文献

Butterflies are declining globally, mainly due to expansion and abandonment of agricultural land. Quantifying the relative importance of agricultural land-use types for butterflies is essential to conservation planning in agricultural landscapes, where land-use changes frequently occur. Here, we surveyed species richness, abundance, and composition in natural lands (wetland and forest), agricultural land, and abandoned agricultural land in two topographic settings (hillslope and lowland) in Hokkaido, northern Japan. The species richness and abundance of open-land butterflies tended to be the highest in agricultural lands in both topographic settings. Although those of communities were lowest in natural lands, such areas had unique species compositions. Topography can be an important factor explaining the variation in species richness and abundance among abandoned agricultural lands. In hillslope areas, abundance of open-land butterflies was lower in abandoned agricultural lands than in active ones. In lowland areas, however, species richness and abundance of abandoned agricultural lands were comparable to those of active ones in both communities and functional groups. Our results suggest that both topography and land-use type have significant effects on butterfly community composition in agricultural landscapes.

The golden orchid Cephalanthera falcata is on the verge of extinction from Japan due to foraging by the agromyzid fly Japanagromyza tokunagai and the decline of pollinator bees. Artificial pollination and bagging treatments that exclude foraging flies are promising conservation measures. I examined the rates of fruit set and ripe seed production resulting from the artificial pollination and bagging of C. falcata at one field site in Fukui Prefecture, Japan. I tested 13 individuals over 3 years from 2021 to 2023, classified into three treatment groups: (1) no artificial pollination + no bagging (8 individuals), (2) artificial pollination + no bagging (3 individuals), and (3) artificial pollination + bagging (2 individuals). Artificial pollination resulted in an average of 4 fruits per individual (range: 1–6 fruits), while untreated plants produced 2.1 fruits on average (range: 1–6 fruits; Wilcoxon’s rank sum test, p = 0.151). Additionally, the mean damage rate per individual, which was calculated as the proportion of fruits damaged by J. tokunagai out of all fruits, was 0% in the bagged group and 100% in the untreated group (Wilcoxon’s rank sum test, p < 0.001). Thus, the bagging of C. falcata produced statistically significant improvements in ripe seed production. However, artificial pollination of C. falcata did not produce statistically significant improvements in fruit set production. My results suggest that fruit set production is not affected by artificial pollination for C. falcata. The damage of C. falcata by J. tokunagai is quite noticeable, with serious implications for the species’ ongoing reproduction and survival.

Human activities affect all ecosystems, within that the grasslands have often been subject to intensive modification due to agricultural use and fragmentation. The result is a biodiversity crisis, on which detailed agri-environment schemes can help. For the compilation of perspective schemes, it is crucial to know the minimal area that can provide habitats for stable, species-rich insect assemblages in optimal land use.

This research aimed to collect detailed data for phrasing patch-size centric conservation strategies on orthopteran assemblages, being an umbrella taxon, in two areas of the Pannonian Ecoregion. In narrow (radius = 25 m) and broader (r = 50, 75, 100 m) environments of the assemblages, we have searched for that habitat patch size, where the primary vegetation characteristics (cover, height, composition) affect the main features of the orthopteran assemblages and relative abundances of the species to the highest degree.

According to our results, ecotype diversity of orthopteran assemblages showed the strongest correlations with average maximum grassland height and density at the finest studied scale (r = 25 m). Still, the vegetation heterogeneity significantly determines the life-form diversity of the assemblages in the larger habitat patches. Consequently, a minimum of one hectare-sized well-managed habitat patches are needed to conserve diverse, species-rich orthopteran assemblages. Specific conservation implications are adequate for preserving the main characteristics of the minimal-sized grassland patches under global warming are simulate the traditional low-intensity land use (dominated by mowing diversified both spatially and temporally).

Frogs play crucial roles in ecosystems as both predator and prey within food webs. The decline in their populations is attributed, in part, to modern, intensive rice farming practices. In the Tajima region of Hyogo Prefecture, Japan, a subset of farmers has embraced a “white stork friendly farming” (WSFF) method since 2003, which promotes environment-friendly rice production to preserve and restore biodiversity while aiding the reintroduction of the Oriental White Stork (Ciconia boyciana) into the ecosystem. Here, we hypothesize that the WSFF method has a positive impact on the conservation of black-spotted pond frog (Pelophylax nigromaculatus) populations inhabiting paddy fields. To test this hypothesis, we evaluated the influence of the WSFF method on the population density of P. nigromaculatus. Using a line transect method, we identified and quantified individual frogs observed on the paddy field levees in June 2016. Subsequently, we analyzed the effects of rice production using the WSFF method and land-use factors on the frogs’ population density. Our findings indicate that P. nigromaculatus population density increased with the expansion of paddy-field areas managed under the WSFF method within a 100 m radius of the paddy-field center. These results suggest that rice production following the WSFF method has a positive impact on the conservation of this frog species.

Ecosystem service values are divided into three categories: direct use values, indirect use values, and non-use values. In this research, the economic value of ecosystem services in canola (Brassica napus L.) fields was investigated during 2020–2021. These fields are located in Gorgan County (Sorkhankalateh region) north of Iran. We calculated the carbon sequestration by the carbon emission tax policy as shadow value of carbon, and to estimate some ecosystem services including the oxygen supply, grain yield and soil conservation, we applied the substitute cost methods, direct market method and replacement cost, respectively. Also, the value of pollination service was estimated along with the effect of pollinators on yield production, and the value of agrotourism estimated based on contingent valuation method. In this research, the logit model was used by the maximum likelihood method to investigate the influencing factors on people's willingness to pay. The required data for each of these variables were collected through field methods, questionnaires and face-to-face interviews with 117 visitors from the mentioned region. The results showed that the average total value of ecosystem services was equal to 3,685.91$ ha⁻¹ yr⁻¹. In this research, the value of the provisioning service was equal to 1,720.81$ ha⁻¹. Also, the grain yield had the highest value among ecosystem services and accounted as 46.69 percent of all the ecosystem services. While, atmospheric services (oxygen production and carbon sequestration) included 1,155.12$ (31.34%), pollination 516.24$ (14.01%) and soil conservation 292.19$ (7.93%) of the total economic value. The share of agrotourism service from the total value of services was about 1.53$ (0.04%). In general, canola fields are more important in terms of provisioning services (grain yield) than regulating services such as oxygen production, carbon sequestration, soil conservation and pollination, as well as agrotourism services. Therefore, maintaining and enhancing market and non-market services in the canola fields of the study area is crucial for both the human and economic aspects.

The functional connectivity of nature reserve networks affects species dispersal, conservation effectiveness and even the integrity of local ecosystems. Drastic land transformation might bring about challenges in the formation of nature reserve networks. In this study, we combined land cover data from 1992 to 2020 and terrestrial nature reserves to model potential ecological corridors with the least cost-weighted distance method in Guangdong Province, China. We analyzed the changes in potential ecological corridors and defined the variations in the cumulative cost-weighted distance with long-term land transformation. Inefficient corridors and conservation priorities were also identified. Our results indicate that the number, spatial distribution and patch pairing pattern of potential ecological corridors are affected by the increasing cost-weighted distance. Before 2015, the cost and total length of the potential ecological corridors increased and then decreased until 2020. The variations in potential ecological corridors are induced by the transformation of multiple land covers, with the expansion of croplands and urban areas, and the degradation of shrublands and grasslands. The grids with higher resistance values, namely, urban areas and croplands, in the potential ecological corridors increase, resulting in the increase of the functional connectivity cost. In terms of the composition of potential ecological corridors, compared with urban expansions, the proportion of cropland grids increased slightly but with a larger base and contributed more to the cost increase. Therefore, it is recommended that key ecological corridors and nodes are not to be utilized, which would increase dispersal cost of wild species, and we suggest a more dynamic and integral perspective for effectively managing land resources and designing regional ecological corridors.