农户绿色生产技术采纳行为决策:政策激励还是价值认同?

以湖北省1 086个农户调研数据为研究对象,利用Logit回归模型、中介效应检验模型和调节效应检验模型,围绕政策激励、价值认同对农户有机肥施用行为的影响机制问题进行了深入探讨。结果表明:(1)农户有机肥施用行为受到政策宣传、政府补贴、法规约束、环境危机意识和生态环境改善等多个因素影响;(2)环境危机意识、生态环境改善和农耕文明传承在政策宣传与农户有机肥施用行为之间起中介作用,生态环境改善在法规约束与农户有机肥施用行为之间起中介作用;(3)政府补贴增强了环境危机意识与农户有机肥施用行为之间的正向关系。基于此,创新发展以农业绿色生产为导向的绿色补贴,积极开展当前我国农业发展所面临的形势教育,转变只注重技术如何使用的传统技术推广方式,以便调动农户有机肥施用积极性,实现农业绿色发展。     

农户地膜回收决策影响因素实证研究:基于云南省9个典型农业县的调查数据

地膜是重要的农业生产资料,但长期以来重使用、轻回收,造成我国部分地区地膜残留污染问题日益严重。利用云南省9个典型农业县(区)入户调查获得的963份问卷数据,从认知因素和经济因素2个方面运用二元Logistic回归模型探究农户地膜回收决策影响因素,并分析认知因素和经济因素的主要来源。结果表明:(1)认知因素和经济因素均显著影响农户地膜回收决策,经济因素对农户地膜回收行为的促进作用更大。(2)农户年龄、政府宣传、农户对残膜污染的直接认知、家庭经济状况和政策支持对农户地膜回收决策起正向促进作用;家庭农业从业劳动力人数对农户地膜回收决策起负向促进作用;农户个体特征中性别和文化程度对地膜回收决策的影响不显著。(3)政府宣传和政策支持在农户地膜回收决策中起到关键影响作用。     

农户经济行为方式对农村环境的影响

农户经济行为方式的不同,必然导致不同的环境后果。文章在调查研究的基础上,认为微观上农户的职业选择对于我国广大农户的生产方式和生活方式具有重要影响,从而间接影响到我国的农村环境状况。我国目前的农村环境状况之所以呈现出种种不同的现状和发展方向,最直接的原因,是由于不同的农户经济行为方式选择所造成的。因此,进行农村环境保护,离不开对农户生存状态的认识和研究,只有从根本上提高和改善农户的生存状态,才能达到持续利用与保护农村环境的最终目标。     

《农村生态环境》稿约

1　《农村生态环境》系国家环境保护总局南京环境科学研究所主办、中国环境科学出版社出版的学术期刊 ,是全国中文核心期刊 ,中国科学引文数据库来源期刊 ,中国学术期刊综合评价数据库来源期刊。本刊宗旨是及时报道生态环境保护领域研究的动态、理论、方法和成果。主要内容包括 :( 1)全球重大环境问题的生态影响 ;( 2 )生态功能区、自然保护区、生态示范区的建设和管理的研究 ;( 3 )自然资源开发和可持续发展理论与模式 ;( 4)生态破坏和环境污染控制的理论与方法 ;( 5 )生物多样性保护与生态安全性研究 ;( 6)农村和城镇生态系统的优化研究 ;…     

《农村生态环境》稿约

1　《农村生态环境》系国家环境保护总局南京环境科学研究所主办、中国环境科学出版社出版的学术期刊,是全国中文核心期刊,中国科学引文数据库来源期刊,中国学术期刊综合评价数据库来源期刊。本刊宗旨是及时报道生态环境领域学术研究的动态、理论、方法和成果。主要内容包括:(1)全球重大环境问题的生态学影响;(2)自然保护、自然资源开发和可持续发展的研究;(3)转基因生物产品的生物安全性研究;(4)生态破坏与环境污染控制的理论与方法;(5)农村与城镇生态系统的优化模式研制;(6)农村生态环境管理及相关政策的研究。欢迎从事生态、环境和资源研…     

基于条件估值法(CVM)的湿地周边农户受偿意愿及影响因素研究:以江苏盐城珍禽自然保护区为例

生态补偿是应对生物多样性保护问题的有效环境政策。作为主要利益相关者的农户,其参与意愿直接影响生态补偿项目实施的绩效与可持续性。在调查盐城潮滩湿地生态环境基础上,以支付卡方式设计调查问卷,采取面对面方式对保护区周边125个农户进行调查,基于条件估值法(contingent valuation method,CVM)估算其生态补偿的受偿意愿,选择农户的性别、年龄、家庭年收入等基本社会经济特征,以农户对生态补偿了解程度和生态补偿态度为自变量,以农户受偿意愿为因变量,运用二项Logistic模型分析影响当地农户受偿意愿的相关因素。结果表明,保护区周边农户具有一定的湿地生态环境保护认知和意识;有88%的农户选择非零补偿意愿,平均受偿意愿为7 727. 7元·hm-2·a-1。Logistic模型分析结果表明农户的年龄、拥有的耕地面积和对生态补偿了解程度是影响其受偿意愿的主要因素。农户年龄越大,其受偿意愿相对降低;农户拥有的耕地面积越小,受偿意愿就越大;对生态补偿了解程度越高,生态补偿意愿就越强。研究结果可为保护区生态补偿政策的有效落实提供科学支持,也可为其他保护区生态补偿的实施提供借鉴。     

《农村生态环境》稿约

1　《农村生态环境》系国家环境保护总局南京环境科学研究所主办、中国环境科学出版社出版的学术期刊 ,是全国中文核心期刊 ,中国科学引文数据库来源期刊 ,中国学术期刊综合评价数据库来源期刊 ,并被CA、CAB和AGRIS等国外文摘和数据库收录。本刊宗旨是及时报道生态环境保护领域研究的动态、理论、方法和成果。主要内容包括 :(1 )全球重大环境问题的生态影响 ;(2 )生态功能区、自然保护区、生态示范区的建设和管理的研究 ;(3)自然资源开发和可持续发展理论与模式 ;(4)生态破坏和环境污染控制的理论与方法 ;(5 )生物多样性保护与生态安全…     

内在感知、外部环境对农户绿色施肥技术采纳行为的影响研究

作为化肥施用的决策主体,农户绿色施肥技术采纳决策和采纳程度受内在感知和外部环境的双重影响。系统分析农户绿色施肥技术采纳行为对推动农业绿色高质量发展具有重要的理论和现实意义。基于山东省苹果种植户680份实地调研微观数据,运用Heckman模型实证分析了内在感知和外部环境对农户绿色施肥技术采纳决策和采纳程度的影响及差异。研究结果表明：(1)农户对绿色施肥技术的采纳决策存在“高意愿、低行动”现象,且平均采纳程度不高;(2)技术感知显著正向影响农户绿色施肥技术采纳行为,经济价值对农户绿色施肥技术采纳行为的影响明显大于社会价值和生态价值;(3)表征外部环境的指令性规范和示范性规范均显著正向影响农户绿色施肥技术采纳决策,生态补偿对其采纳程度具有显著影响。因此,为激励农户绿色施肥技术采纳行为的积极性和主动性,应加大绿色施肥技术的宣传教育,积极培育新型农业经营主体,提高农户采纳绿色施肥技术的内在动力。     

贸易对环境的影响：主要问题和挑战

对贸易与环境之间相互作用的了解的加深产生了制定环境保护手段和贸易手段的新方法，这篇文章回顾了有关贸易与环境关系的理论和实验性工作，中心内容是经济全球化和贸易自由化的环境影响（正面的和负面的）。文章还探讨了它们对贸易和环境政策的影响。     

贸易对环境的影响:主要问题和挑战

对贸易与环境之间相互作用的了解的加深产生了制定环境保护手段和贸易手段的新方法.这篇文章回顾了有关贸易与环境关系的理论和实验性工作.中心内容是经济全球化和贸易自由化的环境影响(正面的和负面的).文章还探讨了它们对贸易和环境政策的影响.     

Rapid,recurring, structured survey versus bioblitz for generating biodiversity data and analysis with a multispecies abundance model

A bioblitz inexpensively and quickly generates biodiversity data, but bioblitzes are often conducted with haphazard, unreplicated sampling. Results tend to be taxonomically, geographically, or temporally biased, lack metadata, and consist of lists of observed taxa that do not enable further analyses or correction for imperfect detection. A rapid, recurring, structured survey (RRSS) uses a structured sampling design and temporal and spatial replication to survey randomly selected sites on a conservation property. We participated in a loosely structured bioblitz and a subsequent RRSS at Big Canoe Creek Nature Preserve in Springville (St. Clair County), Alabama (USA) to compare observed richness derived from the 2 survey approaches. The RRSS data structure enabled us to fit models that accounted for imperfect detection to estimate abundances, occupancy probabilities, and habitat associations. The loosely structured bioblitz data could not be used in such models. We present a new integrated multispecies abundance model that we applied to avian RRSS data. Our model extension enables estimation for the community, employs data augmentation to estimate the number of undetected species, and incorporates covariates. The RRSS generated a more comprehensive and less biased list of observed taxonomic richness than the loosely structured bioblitz (e.g., 73 vs. 45 bird species and 104 vs. 63 insect families from the RRSS vs. loosely structured bioblitz, respectively). Models fit to the RRSS data identified seasonal patterns in avian community composition and allowed for estimation of habitat–occupancy relationships for insect taxa. The RRSS protocol has potential for broad transferability as a standardized, quick, and inexpensive way to inventory biodiversity and estimate ecological parameters while providing an outreach opportunity.     

Compliance with and ecosystem function of biodiversity offsets in North American and European freshwaters

Land-use change via human development is a major driver of biodiversity loss. To reduce these impacts, billions of dollars are spent on biodiversity offsets. However, studies evaluating offset project effectiveness that examine components such as the overall compliance and function of projects remain rare. We reviewed 577 offsetting projects in freshwater ecosystems that included the metrics project size, type of aquatic system (e.g., wetland and creek), offsetting measure (e.g., enhancement, restoration, and creation), and an assessment of the projects’ compliance and functional success. Project information was obtained from scientific and government databases and gray literature. Despite considerable investment in offsetting projects, crucial problems persisted. Although compliance and function were related to each other, a high level of compliance did not guarantee a high degree of function. However, large projects relative to area had better function than small projects. Function improved when projects targeted productivity or specific ecosystem features and when multiple complementary management targets were in place. Restorative measures were more likely to achieve targets than creating entirely new ecosystems. Altogether the relationships we found highlight specific ecological processes that may help improve offsetting outcomes.     

A palaeo-hydrogeological model for arsenic contamination in southern and south-east Asia

An argument is presented in which areas of natural arsenic contamination of modern groundwaters throughout Asia have a common origin. Arsenic originally accumulated in oceanic ferro-manganoan sediments of the eastern Palaeo-Tethys. This was further concentrated through oceanic crustal extinction in what later became the south-east Chinese accreted mineralised terrain. Proto-Himalayan uplift of this area created the palaeo-drainage systems of the Ganges – Brahmaputra, Irrawaddy, Mekong, and Red Rivers, with consequent headwater erosion of arsenic-rich sediments. Their downstream deposition as immature and easily redistributed Neogene sandstones, silts, and iron-rich clays has created secondary and tertiary reservoirs of adsorbed and authigenic arsenic, from which the current arsenic-rich groundwaters have evolved. Considering river basins within the above palaeo-hydrogeological framework provides a basis for assessing the risk of arsenic in groundwater basins of south and south-eastern Asia.     

Cost‐effective conservation of an endangered frog under uncertainty

How should managers choose among conservation options when resources are scarce and there is uncertainty regarding the effectiveness of actions? Well‐developed tools exist for prioritizing areas for one‐time and binary actions (e.g., protect vs. not protect), but methods for prioritizing incremental or ongoing actions (such as habitat creation and maintenance) remain uncommon. We devised an approach that combines metapopulation viability and cost‐effectiveness analyses to select among alternative conservation actions while accounting for uncertainty. In our study, cost‐effectiveness is the ratio between the benefit of an action and its economic cost, where benefit is the change in metapopulation viability. We applied the approach to the case of the endangered growling grass frog (Litoria raniformis), which is threatened by urban development. We extended a Bayesian model to predict metapopulation viability under 9 urbanization and management scenarios and incorporated the full probability distribution of possible outcomes for each scenario into the cost‐effectiveness analysis. This allowed us to discern between cost‐effective alternatives that were robust to uncertainty and those with a relatively high risk of failure. We found a relatively high risk of extinction following urbanization if the only action was reservation of core habitat; habitat creation actions performed better than enhancement actions; and cost‐effectiveness ranking changed depending on the consideration of uncertainty. Our results suggest that creation and maintenance of wetlands dedicated to L. raniformis is the only cost‐effective action likely to result in a sufficiently low risk of extinction. To our knowledge we are the first study to use Bayesian metapopulation viability analysis to explicitly incorporate parametric and demographic uncertainty into a cost‐effective evaluation of conservation actions. The approach offers guidance to decision makers aiming to achieve cost‐effective conservation under uncertainty.     

Parasitic wasps orient to green leaf volatiles

Summary Undamaged plants emit low levels of green leaf volatiles (GLVs), while caterpillar-damaged and artificially damaged plants emit relatively higher levels of certain GLVs. Female braconid parasitoids,Microplitis croceipes, oriented to both damaged plants and to individual GLVs in no-choice tests in a wind tunnel, but seldom oriented to undamaged plants. Female ichneumonid parasitoids,Netelia heroica, also oriented to individual GLVs in a wind tunnel. Males of both wasp species failed to orient to the GLVs. These data show that leaf-feeding caterpillars can cause the release of GLVs, and that parasitic wasps can respond to these odors by flying upwind (chemoanemotactic response), which brings the wasps to their caterpillar hosts. This supports the hypothesis that plants communicate with members of the third trophic level,i.e., plants under herbivore attack emit chemical signals that guide natural enemies of herbivores to sites of plant damage. In this interaction, the GLVs serve as tritrophic plant-to-parasitoid synomones. That parasitoids from two different wasp families oriented to GLVs suggests that the response may be widespread among the Hymenoptera.Mention of a commercial or proprietary product does not constitute an endorsement by the U.S. Department of Agriculture     

Potential for Electropositive Metal to Reduce the Interactions of Atlantic Sturgeon with Fishing Gear

Atlantic sturgeon (Acipenser oxyrhynchus) populations have been declared either endangered or threatened under the U.S. Endangered Species Act. Effective measures to repel sturgeon from fishing gear would be beneficial to both fish and fishers because they could reduce both fishery‐associated mortality and the need for seasonal and area closures of specific fisheries. Some chondrostean fishes (e.g., sturgeons and paddlefishes) can detect weak electric field gradients (possibly as low as 5 Μv/cm) due to arrays of electroreceptors (ampullae of Lorenzini) on their snout and gill covers. Weak electric fields, such as those produced by electropositive metals (typically mixtures of the lanthanide elements), could therefore potentially be used as a deterrent. To test this idea, we recorded the behavioral responses of juvenile Atlantic sturgeon (31–43 cm fork length) to electropositive metal (primarily a mixture of the lanthanide elements neodymium and praseodymium) both in the presence and absence of food stimuli. Trials were conducted in an approximately 2.5 m diameter × 0.3 m deep tank, and fish behaviors were recorded with an overhead digital video camera. Video records were subsequently digitized (x, y coordinate system), the distance between the fish and the electropositive metal calculated, and data summarized by compiling frequency distributions with 5‐cm bins. Juvenile sturgeon showed clear avoidance of electropositive metal but only when food was present. On the basis of our results, we conclude that the electropositive metals, or other sources of weak electric fields, may eventually be used to reduce the interactions of Atlantic sturgeon with fishing gear, but further investigation is needed. El Potencial del Metal Electropositivo para Reducir las Interacciones del Esturión Atlántico con Instrumentos de Pesca Bouyoucos, Bushnell & Brill 13–003     

The role of time and species identities in spatial patterns of species richness and conservation

Many conservation actions are justified on the basis of managing biodiversity. Biodiversity, in terms of species richness, is largely the product of rare species. This is problematic because the intensity of sampling needed to characterize communities and patterns of rarity or to justify the use of surrogates has biased sampling in favor of space over time. However, environmental fluctuations interacting with community dynamics lead to temporal variations in where and when species occur, potentially affecting conservation planning by generating uncertainty about results of species distribution modeling (including range determinations), selection of surrogates for biodiversity, and the proportion of biodiversity composed of rare species. To have confidence in the evidence base for conservation actions, one must consider whether temporal replication is necessary to produce broad inferences. Using approximately 20 years of macrofaunal data from tidal flats in 2 harbors, we explored variation in the identity of rare, common, restricted range, and widespread species over time and space. Over time, rare taxa were more likely to increase in abundance or occurrence than to remain rare or disappear and to exhibit temporal patterns in their occurrence. Space–time congruency in ranges (i.e., spatially widespread taxa were also temporally widespread) was observed only where samples were collected across an environmental gradient. Fifteen percent of the taxa in both harbors changed over time from having spatially restricted ranges to having widespread ranges. Our findings suggest that rare species can provide stability against environmental change, because the majority of species were not random transients, but that selection of biodiversity surrogates requires temporal validation. Rarity needs to be considered both spatially and temporally, as species that occur randomly over time are likely to play a different role in ecosystem functioning than those exhibiting temporal structure (e.g., seasonality). Moreover, temporal structure offers the opportunity to place management and conservation activities within windows of maximum opportunity.     

Main nutrient compounds in food bodies of Mexican <Emphasis Type="Italic">Acacia</Emphasis> ant-plants

Summary. Myrmecophytic plants use obligate ant mutualists as a constitutive indirect defence mechanism. These plants often produce cellular food bodies (FBs) to nourish their resident ants. Lipids, proteins, and even highly specialised compounds such as glycogen have been reported from FBs, but detailed chemical analyses of FB composition have so far been presented only for Southeast Asian Macaranga and Central American Piper myrmecophytes. Here we report the chemical composition of FBs of five myrmecophytic Acacia (Fabaceae) species from Mexico using HPLC (carbohydrates and proteins) and GC-MS (lipids). Feeding experiments revealed no hints on any use of external food sources by the inhabiting Pseudomyrmex ants. These ants obviously rely completely on FBs and extrafloral nectar provided by their hosts. The total content of nutrients in Acacia FBs was 15-25% of FB dry mass, being much lower than in Macaranga or Piper FBs. Proteins were dominating (8-14 % dm) in Acacia FBs and thus were present in higher amounts than in Macaranga FBs, yet in lower amounts than in Piper. Lipids contributed 1-9 % of dry mass, showing a lower proportion than in FBs of Macaranga or Piper. Carbohydrates made up 3-11 % dm, reaching in most Acacia species the same range as observed in Macaranga and in Piper FBs. Water content was 18-24 % of FB fresh mass, and structural tissue obviously made up a much higher proportion in Acacia FBs than in Macaranga or Piper FBs. Both characters might represent an adaptation to producing FBs unprotected at the leaf tips under dry conditions. Acacia FBs contain all amino acids and all fatty acids that are considered essential for insects, and their contents of lipids and proteins are higher than in the leaves from which they are ontogenetically derived. This indicates a putatively adaptive enrichment of nutritionally valuable compounds in structures functioning as ant-food.     

Examining the uncertain origin and management role of martens on Prince of Wales Island,Alaska

Conservation biologists are generally united in efforts to curtail the spread of non‐native species globally. However, the colonization history of a species is not always certain, and whether a species is considered non‐native or native depends on the conservation benchmark. Such ambiguities have led to inconsistent management. Within the Tongass National Forest of Alaska, the status of American marten (Martes americana) on the largest, most biologically diverse and deforested island, Prince of Wales (POW), is unclear. Ten martens were released to POW in the early 1930s, and it was generally believed to be the founding event, although this has been questioned. The uncertainty surrounding when and how martens colonized POW complicates management, especially because martens were selected as a design species for the Tongass. To explore the history of martens of POW we reviewed other plausible routes of colonization; genetically and isotopically analyzed putative marten fossils deposited in the late Pleistocene and early Holocene to verify marten occupancy of POW; and used contemporary genetic data from martens on POW and the mainland in coalescent simulations to identify the probable source of the present‐day marten population on POW. We found evidence for multiple routes of colonization by forest‐associated mammals beginning in the Holocene, which were likely used by American martens to naturally colonize POW. Although we cannot rule out human‐assisted movement of martens by Alaskan Natives or fur trappers, we suggest that martens be managed for persistence on POW. More generally, our findings illustrate the difficulty of labeling species as non‐native or native, even when genetic and paleo‐ecological data are available, and support the notion that community resilience or species invasiveness should be prioritized when making management decisions rather than more subjective and less certain conservation benchmarks.